SSD21

Final Program

Sunday June 8, 2025


16:00 - 22:00	Registration and Reception

Monday June 9, 2025

Presented author:
Yuka Miyamoto-Yanagida - Chiyoda Technol Corporation

Authors:
1.-Yuka Miyamoto-Yanagida, Chiyoda Technol Corporation, Japan 2.-Naoki Takashima, Chiyoda Technol Corporation, Japan 3.-Yuichi Kitagawa, Horiba Techno Service Co., Ltd., Japan 4.-Yasuhiro Koguchi, Chiyoda Technol Corporation, Japan 5.-Toshio Kurobori, Chiyoda Technol Corporation, Kanazawa University, Japan

Ag-doped phosphate glass is a potential material as a detector in radiation dosimetry in the dose range between 10 µGy and 10 Gy. An investigation on optical properties and unique behaviour of radiophotoluminescent (RPL) centres in Ag-doped phosphate glass irradiated with high-dose 60Co gamma-rays was presented. We obtained a corrected 3D matrix representing the true excitation and emission spectra using the absorbance-transmittance excitation-emission matrix technique. Further, we analysed the radiative lifetimes and wavelength components, as observed in the steady-state fluorescence emission with 1- and 0.3 mm-thick glass plates. This study revealed the mechanism behind the formation of green RPL at a wavelength of 530 nm, which has not been examined in previous studies. By tracking the changes in RPL intensity, fluorescence lifetimes, and peak wavelength shifts as a function of gamma-ray in the dose range of 50 Gy to 50 kGy, we discovered that blue, green, orange, red, and near-infrared RPL exhibit complex behaviours, such as reduction, enhancement, disappearance, and emergence, while preserving their spectral profiles. We demonstrated that Ag-doped phosphate glass irradiated with high-dose gamma-rays with a low linear energy transfer (LET) value (~0.2 keV/µm) exhibited the formation of new RPL centres, specific optical properties, and the mechanisms that were not observed at lower doses (on the order of tens of Gy). In addition, a reduction in the efficiency of orange RPL (known as ‘LET quenching’), which is typically observed with the irradiation high LET alpha particles and heavy charged particles, was detected. Such behaviour was also observed in the dose dependence of the orange (~ 650 nm)-to-blue (~ 450 nm) RPL intensity ratio in the high-dose region when irradiated with low LET gamma-rays. We believe that the findings of this study will be helpful for evaluating LET value, which determines the biological consequences due to exposure to radiation.

Presented author:
Alicja Chruścińska - Nicolaus Copernicus University

Authors:
1. Alicja Chruścińska, Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University in Toruń, Grudziądzka 5, 87-100 Toruń, Poland 2. Marcin E. Witkowski, Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University in Toruń, Grudziądzka 5, 87-100 Toruń, Poland, 3. Natalia K. Pawlak, Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University in Toruń, Grudziądzka 5, 87-100 Toruń, Poland,

In stimulated luminescence (SL) studies, we create models to understand the mechanisms of observed effects and describe them quantitatively. We value models that allow us to determine the parameters of the centres involved in the processes under consideration. Due to SL applications in dosimetry, the thermal stability of traps responsible for individual luminescent signals is crucial. Hence, the most commonly exploited are kinetic models based on the energy band model, which allow for the description of measurement curves by analytical functions with the thermal activation energy and the frequency factor of traps as the parameters. One uses these functions to decompose SL curves into components derived from individual trap types and obtains excellent agreement of the sum of the components with the experimental curves by applying fitting procedures. Therefore, it may be disappointing when the trap parameters determined in this way lead to incorrect predictions of other experimental results. There may be many potential reasons for obtaining wrong parameters from fittings. Apart from the first, a trivial one, which is using an inappropriate model, some physical mechanisms may be important, such as trap coupling effects, luminescent centre competition, or thermal quenching. Other problems are related to the experimental technique, such as the choice of the spectral window for luminescence detection or, generally speaking, the consistency of the actual stimulation with this assumed in the model. In analysing SL measurement results, fitting procedures using modelling, i.e. fitting of theoretical curves that are numerical solutions of the kinetic equation system corresponding to the selected model, are becoming increasingly common. Given the availability and rapid development of tools enabling such analysis, this fitting type will likely soon become dominant. Its advantage is that the competition of traps and recombination centres is inscribed in the solved equations. Effects such as thermal quenching or the dependence of parameters on temperature (e.g., the optical cross-section of the trap in OSL) can be included, considering the results of independent experiments. However, it is worth remembering that, regardless of the improvement of computational techniques, the reasons for obtaining incorrect parameters in simulations resulting from a superficial reconstruction of the experiment remain the same. In addition to SL curves, an essential object of modelling is the dependency of the components of these curves on the radiation dose (dose-response curves), on the preheating temperature (pulse annealing curves), on the time of storage (isothermal signal decay) or optical bleaching. To determine theoretical dependencies, it is often necessary to model many processes occurring during successive steps of measurement procedures. Modelling this type requires considering not only all steps of an applied procedure but also the sample history, which affects the occupation of the deepest traps and the redistribution of holes in recombination centres. The presentation will reveal examples of modelling the SL processes within the categories of their applications mentioned above. Their potential for interpreting measurement results and issues that must be included if the interpretation is to be reliable will be discussed.

Presented author:
Alejandro Ibarra Vega - UNAM

Authors:
Alejandro Ibarra-Vega, Instituto de Física, Universidad Nacional Autónoma de México, 04510 Mexico City, México. Lorenzo Stella, Centre for Light-Matter Interactions (CLMI), Queen’s University Belfast, Belfast, BT7, 1NN, Northern Ireland, UK. Jorge Kohanoff, Instituto de Fusión Nuclear “Guillermo Velarde”, Universidad Politécnica de Madrid, 28006, Madrid, Spain. Guerda Massillon-JL, Instituto de Física, Universidad Nacional Autónoma de México, 04510 Mexico City, México.

During the last decades aluminum oxide (Al2O3) becomes one of the most common optically stimulated luminescent dosimeter for personnel dose monitoring and in vivo dosimetry. Like many other dosimeters, at photon energy beams below 100 keV, Al2O3 is strongly energy dependent. One of the main problems at this energy range, is the lack of information regarding the interaction process of low-energy secondary electrons generate. Density functional theory (DFT) has been shown to be a reliable tool to study the interaction of radiation with dosimetric materials. In this work, first-principles calculations based on DFT were performed to study, at the atomic level, the defect states generate in Al2O3 upon irradiation and their relationship with the energy deposition. The simulations were carried out using the open-source code CP2K for a 3×3×3 (810 atoms) and a 3×3×2 (540 atoms) supercells of the pristine Al2O3 at the PBE level using the DZVP-MOLOPT-SR-GTH basis set. The preliminary results indicated an energy gap of 6.24 eV consistent with other reported theoretical results (6.29 eV) but, lower than the experimental gap of 8.7 eV obtained through optical spectroscopy. This value is not surprising since it is well known that the PBE generally underestimates the band gap. As we reported previously, for a better comparison with experiments, hybrid functionals such as PBE0 will be used to improve the accuracy in estimating the band gap before adding dopants and radiation to the system. Such calculations will contribute to a better understanding of the Al2O3 response to low-energy radiation. We acknowledge computational support from Miztli UNAM Mexico through grant ref. LANCAD-UNAM-DGTIC-334. This project is partially supported by the European Commission Horizon MSCA-SE Project MAMBA (Grant No.101131245) and PAPIIT-UNAM (Grant No. IN106825).

Presented author:
Devesh R. Mishra - Bhabha Atomic Research Center Mumbai INDIA

Authors:
D. R. Mishra, Bhabha Atomic Research Centre,Mumbai, India

The developments in solid-state radiation dosimetry have focused on enhancing sensitivity, precision, and adaptability to various radiation environments, including personal monitoring, medical applications, and space radiation protection. Considering present radiation measurements challenges, it is valuable to highlights the key advancements in both passive and active Solid-State Radiation Dosimetry (SSRD). For passive SSRD, progress in Thermoluminescence (TL) and Optically Stimulated Luminescence (OSL) phosphors, nanotechnology, and micro-dosimetry techniques, along with associated instrumentation, will be discussed. Plastic and glass dosimeters and track-etch detectors like CR39 are also explored. Silicon carbide (SiC) and diamond-based dosimeters are emerging as promising passive dosimetry solutions due to their capability to record cumulative radiation doses in harsh environments, such as space and nuclear reactors. Their high radiation tolerance makes them ideal for long-term passive monitoring without degradation, a topic of significant interest. In active SSRD, recent advancements include semiconductor-based dosimeters, scintillators, and real-time and wireless dosimetry. Innovations in real-time OSL, radio-photo luminescent (RPL), and MOSFET dosimeters will be covered. The integration of AI and hybrid dosimetric systems, combining passive and active elements, allows for both real-time monitoring and post-exposure analysis. Passive elements provide cumulative dose data, while active components (such as complementary digital or analog sensors) enable real-time alerts if dose limits are exceeded. This combination is especially valuable in critical fields like nuclear power and space exploration, where continuous radiation monitoring and dose accumulation tracking are essential. These advances also open new possibilities for high LET radiation dosimetry, particularly for human space missions. Addressing the challenges of reliable and robust radiation measurement requires a detailed analysis of these SSRD systems. On the front, real-time remote monitoring using wireless dosimeters is becoming common in industries with radiation exposure risks. These devices can transmit real-time data to central monitoring stations, enabling continuous observation without the need for physical retrieval. Integrating Semiconductor-based Solid-State Radiation Detectors (SSRD) with AI tools promises enhanced dosimetry capabilities across diverse applications, including medical environments, nuclear reactors, strategic operations, and space missions. The highlighted advancements in SSRD technology require extensive discussion and further development within the global scientific community. Addressing these needs would help fill remaining gaps in radiation measurement, especially in areas where traditional methods face limitations.

Presented author:
Patrícia Nicolucci - University of São Paulo

Authors:
1.- Patrícia Nicolucci, University of São Paulo, Brazil 2.- Angela Kinoshita, University of Western São Paulo, Brazil 3.- Marcos Candeias, Eletronuclear, Brazil 4.- Oswaldo Baffa, University of São Paulo, Brazil

The Brazilian Nuclear Power Plant (NPP) Angra 1 has been running an Environmental Qualification Program of Electric Equipment (EQPEE) to to assess the feasibility of extending its operational lifespan. The radiation doses to electrical equipment must be evaluated as part of the EQPEE. In this work, Electron Spin Resonance (ESR) and Thermoluminescent (TL) dosimetry were used to assess the doses in electric cables and equipment at strategic positions in the vicinity of the nuclear reactor at Angra 1. Alanine dosimeters were used for ESR dosimetry and TLD-100 (LiF:Mg,Ti) was used for TL dosimetry. Alanine was used in expected high-dose spots, whereas alanine and TLD-100 were positioned in lower dose areas outside the reactor contention. The dosimeters were shielded from ambient conditions within 5 mm-thick polyacetal containers that also served as buildup layers. All the dosimeters remained in the NPP for an approximate 1-year operation cycle. The dosimeters were calibrated in a 137Cs beam. Temperatures at the same spots of the dosimeters were also monitored and were always below 35oC. Sensitivity of alanine and TLD-100 for 137Cs were, respectively, (7.9 ± 0.8) spins(a.u.)/Gy and (74.2 ± 2.1) nC/mGy. The relative sensitivity for alanine and TLD-100 for the in-site energy spectrum to the calibration spectrum were 0.96 and 0.98, respectively. Doses lower than 0.5 Gy were obtained at several positions and high-dose areas reached up to approximately 7.5 kGy. ESR and TL dosimetry proved to be useful in assessing doses in a complementary range of doses to electric cables and equipment at a NPP. Moreover, the use of different dosimetry methodologies and materials can assist the NPPs’ administrations in assertively establishing lifetime extension conditions. Financial Support: CEPID-NEUROMAT, 2015-18221-9, São Paulo Research Foundation (FAPESP) Grant 2018/05982-0, CAPES Finance Code 001 and National Council for Research and Technological Development (CNPq) Grant 305827/2023-5 and 306096/2023-4.

Presented author:
Wei-Sin Chen - National Tsing Hua University

Authors:
1. Wei-Sin Chen, Department of Biomedical Engineering & Environmental Sciences, National Tsing-Hua University, Taiwan, ROC 2. Yi-Shiuan Chen, Department of Radiation Protection, National Atomic Research Institute, Taiwan, ROC 3. Ching-Han Hsu, Department of Biomedical Engineering & Environmental Sciences, National Tsing-Hua University, Taiwan, ROC 4. Fang-Yuh Hsu1, Nuclear Science and Technology Development Center, National Tsing Hua University, Taiwan, ROC

Introduction In August 2023, Japan began discharging tritium-containing treated water from the Fukushima nuclear accident into the ocean. Besides, China has been constructing numerous nuclear reactor units along its coastal areas, tritiated wastewater also may be released into the ocean during routine nuclear power plant operations. This study focuses on deriving recommended activity concentration values for radionuclides of concern in the seawater around Taiwan, including tritium, cesium-134, cesium-137, and strontium-90. Methods This study first collected relevant lifestyle parameters of Taiwan’s representative population, and used seawater activity concentration monitoring data from the surrounding marine areas as the source term for dose assessment. The potential radiation dose and corresponding cancer risk to Taiwan's representative individuals due to such marine radiation incidents were calculated. Subsequently, recommended activity concentration values for radionuclides of concern in the seawater around Taiwan were derived. The derivation process incorporated methods used internationally for determining recommended activity concentration values of radionuclides in drinking water. Results The assessed radiation dose received by representative individuals in Taiwan is approximately 3.57x10^-4 mSv/a, which is significantly lower than the public dose limit of 1 mSv/a stipulated by Taiwan's Ionizing Radiation Protection Act. Additionally, this study recommends the following seawater activity concentration values for radionuclides of concern in the marine environment around Taiwan: tritium at 100,000 Bq/L, cesium-134 at 10 Bq/L, cesium-137 at 10 Bq/L, and strontium-90 at 10 Bq/L. Conclusions If a marine radiation incident occurs in the seawaters surrounding Taiwan in the future, the seawater activity concentration values of the radionuclides of concern suggested in this study can be used as a reference to determine whether there is localized radiation contamination in the seawaters surrounding Taiwan.

Presented author:
Carles Domingo - Universitat Autònoma de Barcelona

Authors:
1.- R. Domingo-Roca, University of Strathclyde, U.K. 2.- M. Moraleda, CIEMAT, Spain 3.- I. Sarasola, CIEMAT, Spain 4.- C. Domingo, UAB, Spain 5.- J.M. Gómez-Ros, CIEMAT, Spain

Neutron personal dosimetry is essential for monitoring workers exposed to neutron radiation, from those in the nuclear industry to surgeons and other healthcare professionals. In addition, the growth of protons and heavy ions therapy techniques, where neutrons are originated as parasitic radiation without therapeutic effect, makes necessary to measure neutron doses in patients. Consequently, new techniques and devices are continuously being developed and refined to increase sensitivity to a wider range of energies. Conventional neutron detectors have long been used to measure neutron radiation, but most of them are bulky and have limited sensitivity across a broad range of neutron energies, particularly with lower-energy thermal neutrons. Hence, smart solutions are required for the rapid development of compact, lightweight, and versatile neutron detectors. 3D-printing has arisen as a versatile manufacturing technology where small parts (with in-plane resolutions up to 25 microns) can be fabricated with custom materials via light-based approaches, which provide advantages over filament-based approaches in terms of fabrication time and resolution. 3D-printing offers a promising approach to address the limitations associated with neutron detectors enabling the rapid prototyping and customization of neutron detectors with complex geometries. By integrating 3D-printed materials as neutron converters, it is possible to create lightweight, portable detectors with enhanced sensitivity and specific energy ranges, making them suitable for neutron dosimetry applications in varied environments. This work presents the characterization of various thermal neutron sensors by coupling silicon diodes with different 3D-printed converters. The goal is to develop a compact, active detector that offers effective photon discrimination and high sensitivity to thermal neutrons. Acknowledgements: This work has been partially supported by Spanish project NDOSCOR (PID2021-128346NB-C21/C22, cofounded with FEDER). The authors would like also to thank the Engineering and Physical Sciences Research Council (EPSRC) grant number EP/W006456/1, who provided funding to realize part of this work.

Presented author:
Michael Hajek - IAEA

Authors:
R.Cruz Suarez, International Atomic Energy Agency, Austria M Hajek, International Atomic Energy Agency, Austria O. Hupe, Physikalisch-Technische Bundesanstalt, Germany V. Merza, Universidade de Lisboa, Portugal V. Barros, Universidade Federal de Pernambuco, Brazil Y. Koguchi, Chiyoda Technol Corporation, Japan D. Souza-Santos, Instituto de Radioproteção e Dosimetria, Brazil T. Bokulić, University of Zagreb, Croatia E. G. Yukihara, Paul Scherrer Institute, Switzerland

In radiation protection, operational quantities are used for the purpose of measurement of external exposure to ionizing radiation. Those quantities are intended to provide conservative estimates of protection quantities. To account for the known shortcomings in the current definitions, the International Commission on Radiation Units and Measurements (ICRU) Report 95 published in 2020 recommends an alternative approach to the definitions of the operational quantities, based on to the same phantoms that are used to calculate protection quantities. Recognizing the potential benefits of this alternative approach, important questions and concerns need to be addressed to facilitate a decision on adoption and assure continuous trust in the radiation protection system. Evidence of sufficient benefit for workers in general and in specific workplaces is not clear neither proven to all stakeholders. Open questions remain regarding a critical analysis of financial implications, practicality, and impact of the new definitions on radiation protection practices. This paper reviews the current knowledge and identifies knowledge gaps for a more informed discussion on the practical impacts of introducing the ICRU Report 95 operational quantities. Potential implications include a complete redesign of the dosimetry systems and measuring instruments, with all the associated costs, as well as the potential exclusion of simple dosimetry systems relying on one or two detector elements. This work is the result of several consultancy meetings organized by the International Atomic Energy Agency (IAEA) for the preparation of an IAEA technical document (TECDOC) and incorporates the input from various stakeholders.

	Alberto Barajas Celis (ABC) auditorium - Facultad de Ciencias, UNAM
08:30 - 09:00	Open Ceremony
09:00 - 09:30	Key Note María-Ester Brandan - Universidad Nacional Autónoma de Mexico "Keynote address"
09:30 - 10:30	Basic Physical Processes I Moderators: G. Massillon-JL & Stephen McKeever
09:30 - 09:45	Eduardo Yukihara - PSI "Theoretical considerations on the dose-rate dependence of luminescence detectors"
09:45 - 10:00	Yuka Miyamoto-Yanagida - Chiyoda Technol Corporation "Optical properties in Ag-doped phosphate glass irradiated with high doses of gamma-rays"
10:00 - 10:15	Makaiko Chithambo - Rhodes University "Phototransferred thermoluminescence of BeO: Principles, analytical methods and mechanisms"
10:15 - 10:30	Rodolfo Ruiz - Universidad de Sonora "Luminescence and TL properties of Eu3+, Dy3+, Cr3+ co-doped hydroxyapatite (HAp) synthesized by combustion method"
10:30 - 12:00	Poster session and coffee break at the Amoxcalli Lobby - Facultad de Ciencias, UNAM
12:00 - 12:30	Invited Talk 1 Alicja Chruścińska - Nicolaus Copernicus University "Stimulated luminescence modelling - the strengths and weaknesses"
12:30 - 13:30	Basic Physical Processes II Moderators: Eduardo Yukihara & María Ester Brandan
12:30 - 12:45	Stephen W.S. McKeever - Oklahoma State University "Glow Curve Deconvolution – Why are most published results wrong? Common Pitfalls in Measurement and Analysis"
12:45 - 13:00	Gianpaolo Roina - Department of Industrial and Civil Engineering, University of Pisa "Time-Energy distribution of trapped electrons in thermoluminescent LiF:Mg,Cu,P for radiation exposure timestamping"
13:00 - 13:15	Guerda Massillon - Instituto de Física, Universidad Nacional Autónoma de México, 04510 Coyoacan Mexico City "Hydroxide and oxygen on the formation of defect in Ti-doped LiF"
13:15 - 13:30	Alejandro Ibarra Vega - UNAM "A density functional theory study of C-doped Al2O3"
13:30 - 15:00	Lunch at the Physics Institute garden
15:00 - 15:30	Invited Talk 2 Devesh R. Mishra - Bhabha Atomic Research Center Mumbai INDIA "Recent Developments in Solid-State Radiation Dosimetry"
15:30 - 17:00	Monitoring and detection I Moderators: Lily Bossin & Sergii Sholom
15:30 - 15:45	Patrícia Nicolucci - University of São Paulo "ESR and TL Dosimetry for Nuclear Power Plants Environmental Qualification Program of Electrical Equipment"
15:45 - 16:00	Michiko Ube - Chiyoda Technol Corporation "Impact of ICRU Report 95 on the response due to radiation energy and angle of incidence for individual dosemeter with RPL glass"
16:00 - 16:15	Wei-Sin Chen - National Tsing Hua University "Derivation of Recommended Activity Concentration Values for Radionuclides of Concern in Seawater Environmental Monitoring Around Taiwan"
16:15 - 16:30	Carles Domingo - Universitat Autònoma de Barcelona "Silicon based neutron detectors using 3D printed converters"
16:30 - 16:45	Michael Hajek - IAEA "Implications of ICRU Report 95 Operational Quantities for External Radiation Exposure. IAEA actions"
16:45 - 17:00	Anna Cimmino - The Extreme Light Infrastructure ERIC, ELI Beamlines facility "Solid State Dosimeters for Inflight Ambient Dose Measurements: Passive REFLECT"
17:00 - 18:30	Poster session and coffee break at the Amoxcalli Lobby

Presented author:
Iván D. Muñoz - German Cancer Research Center

Authors:
1. Name, Institution, Country 1. I. D. Muñoz, Department of Radiation Oncology, Heidelberg University Hospital (UKHD), Heidelberg, Germany and Division of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany 2. M. Sankowska, Institute of Nuclear Physics, Polish Academy of Sciences (IFJ-PAN), Krakow, Poland 3. A. Kilian, Institute of Nuclear Physics, Polish Academy of Sciences (IFJ-PAN), Krakow, Poland 4. O. Jäkel, Division of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany and Heidelberg Ion-Beam Therapy Center (HIT), Department of Radiation Oncology, Heidelberg University Hospital (UKHD), Heidelberg, Germany 5. P. Bilski, Institute of Nuclear Physics, Polish Academy of Sciences (IFJ-PAN), Krakow, Poland

Several studies have shown that undoped lithium fluoride (LiF) crystals are suitable for use as fluorescent nuclear track detectors (FNTDs), with applications in alpha particle spectrometry and neutron and ion beam dosimetry. To date, however, all research on LiF-based FNTDs has relied on wide-field microscopy. Although confocal microscopy is more time-consuming, it offers superior spatial resolution and noise reduction, potentially improving image quality and detection efficiency. This study explores the detection efficiency and fluorescence intensity of FNTDs exposed to light ions as a function of linear energy transfer (LET), presenting the first results of LiF FNTDs using confocal microscopy and comparing them with those obtained with wide-field microscopy. LiF crystals (3.0 × 3.0 × 0.5 mm3) were exposed to monoenergetic 4He-, 12C-, and 16O-ions. Detectors were placed in plastic boxes (approximately 1.0 mm wall thickness) and attached to a PMMA phantom surface. Additional exposures were conducted at the distal edge of 4He- and 12C- ion spread-out Bragg peaks (SOBPs). To enhance luminescence, a special procedure with annealing crystals at 290°C for 3 min after irradiation was applied [1]. Detection efficiency was close to 100% for 16O-ions at LET_H2O = 50.4 keV/μm and 12C-ions at LET_H2O = 31.8 and 10.6 keV/μm, while a lower efficiency of 50% was observed for 16O-ions at 18.9 keV/μm and 12C-ions at 17.9 keV/μm, which seems to be attributed to less effective sensitivity enhancement of the crystals used for these ion species. For 4He-ions, the efficiency was approximately 30%, due to lower ionization density. Consistent with previous findings, the mean fluorescence intensity of track spots increased with LETH2O. Acknowledgments: IFJ-PAN was supported by the National Science Centre, Poland (grant No 2020/39/B/ST9/00459). [1] M. Sankowska et al., Thermal enhancement of the intensity of fluorescent nuclear tracks in lithium fluoride crystals. Radiat. Meas. 157 (2022) 106845.

Presented author:
José Fernando Diniz Chubaci - Universidade de São Paulo

Authors:
1. Francesco d’Errico, Università di Pisa, Italy 2. Andrea Chierici, Università di Pisa, Italy 3. Riccardo Ciolini, Università di Pisa, Italy 4. Gilson S. Goveia, Università di Pisa, Italy 5. Marina Sparvoli, Universidade de São Paulo, Brazil 6. Jose Fernando Diniz Chubaci, Universidade de São Paulo, Brazil

This research leverages the complementary expertise of UNIPI in neutron detection and USP in solid-state physics to develop an innovative neutron spectrometry system. The system aims to achieve high-resolution neutron energy measurements with reduced noise, autonomous operation, and wireless functionality, addressing limitations in conventional neutron sandwich spectrometry. Our approach replaces lithium-6 with boron-10 as the neutron capture isotope, utilizing boron nitride (BN) grown on silicon carbide (SiC) substrates. BN's wide-bandgap semiconductor properties, combined with SiC’s radiation hardness and thermal stability, enable the creation of an entirely active semiconductor structure. This design improves energy resolution and efficiency by precisely measuring neutron capture events and subsequent reaction energy deposition across BN and SiC layers. The BN/SiC wafers are fabricated at USP using Ion Beam-Assisted Deposition (IBAD), a method allowing precise control of film deposition parameters. IBAD ensures excellent film adhesion, low-temperature deposition, and tunable physical and chemical properties. These attributes enhance the BN/SiC wafers' performance in harsh radiation environments. The electronics subsystem, developed by UNIPI, integrates a Cremat CSA CR-110 charge preamplifier and CR-200 shaping amplifier for signal processing, producing pseudo-Gaussian signals. A multichannel analyzer (MCA) based on an STM32G4 microcontroller digitizes signals with high precision, employing real-time baseline restoration and wireless communication via LoRa. The system is optimized for low power consumption, operating efficiently on an integrated battery or USB, and features thermal-compensated bias stabilization. This compact, portable neutron spectrometry system represents a significant advance in field-ready neutron detection technology. Its development promises applications in radiation monitoring, nuclear safety, and scientific research, addressing critical challenges in resolution and operational efficiency.

Presented author:
Veeraraghavan Akshay Krishnan - Technical University of Denmark

Authors:
1.-Veeraraghavan Akshay Krishnan,Technical University of Denmark, Denmark 2.-Myungho Kook,Technical University of Denmark, Denmark 3.- Andrew Sean Murray, Aarhus University, Denmark 4.- Karsten Bracht Nielsen,Technical University of Denmark, Denmark 5.- Jan-Pieter Buylaert,Technical University of Denmark, Denmark Corresponding author; Email: vakkr@dtu.dk; Telephone: +45-91682646

Commercially available NaI (Tl) based portable gamma spectrometers are commonly used in field measurement to determine burial dose rates of naturally occurring K40, and of the decay series of U238 and Th232. However, these wired gamma spectrometers face limitations in accessing desired measurement locations and may lack the durability needed for rugged environmental conditions. To address this issue, we have developed a wireless field gamma spectrometer, operating on Radio Frequency (RF) and Bluetooth communication. The gamma spectrometer consists of a 2×2-inch NaI scintillator and Silicon Photomultiplier (SiPM). The instrument is developed for wireless communication over both short and long range (upto 25m). It is 35 cm long and weighs 1.56 kg, thus offering easy portability, and has a battery life around 20 hours. The gamma spectrometer was calibrated and tested in the field to assess its performance. Calibration of the gamma spectrometer was performed in calibration facilities, using i) calibration blocks from University of Oxford and ii) borehole/ well logging from DIAMO state enterprise at Stráž pod Ralskem, Czech Republic. The calibration of spectrometer was tested by measuring at the centre of a 1m³ block of granite chips. Sub-samples prepared from 1m³ granite chips were individually measured in lead-shielding using a 3-inch NaI detector. The results of lead-shielded measurements were compared with in-situ measurements of granite chips, to estimate the effectiveness of calibration. The calibrated wireless gamma spectrometer was then used in the field to measure the environmental gamma dose rate component in homogeneous and heterogeneous media with total dose rates ranging from <1 Gy/ka to ~4 Gy/ka.

Presented author:
Massimo Piccinini - ENEA C.R. Frascati

Authors:
1. Massimo Piccinini, ENEA C.R. Frascati, Nuclear Department, Via E. Fermi, 45 - 00044 Frascati (Rome), Italy 2. Adriano Zerbini, ENEA C.R. Frascati, Nuclear Department, Via E. Fermi, 45 - 00044 Frascati (Rome), Italy 3. Alessia Cemmi, ENEA C.R. Casaccia, Nuclear Department, Via Anguillarese, 301 - 00123 S. Maria di Galeria (Rome), Italy 4. Ilaria Di Sarcina, ENEA C.R. Casaccia, Nuclear Department, Via Anguillarese, 301 - 00123 S. Maria di Galeria (Rome), Italy 5. Jessica Scifo, ENEA C.R. Casaccia, Nuclear Department, Via Anguillarese, 301 - 00123 S. Maria di Galeria (Rome), Italy 6. Beatrice D’Orsi, ENEA C.R. Casaccia, Nuclear Department, Via Anguillarese, 301 - 00123 S. Maria di Galeria (Rome), Italy 7. Alessia Embriaco, ENEA C.R. Casaccia, Nuclear Department, Via Anguillarese, 301 - 00123 S. Maria di Galeria (Rome), Italy 8. Maria Aurora Vincenti, ENEA C.R. Frascati, Nuclear Department, Via E. Fermi, 45 - 00044 Frascati (Rome), Italy

Passive solid-state detectors based on lithium fluoride (LiF) crystals, thin films and TLD-100 pellets were irradiated at ten doses in the range from 0.5 to 1000 Gy with the 60Co source of the Calliope irradiation facility at ENEA Casaccia, Italy. The 1 mm-thick LiF crystals and pellets were commercially available, while the LiF films were grown by thermal evaporation on Si(100) substrates, with nominal thickness 2 μm, at ENEA Frascati, Italy. The principle of operation of these radiation detectors is the optical reading of the visible radiophotoluminescence (RPL) emitted by radiation-induced F2 and F3+ color centers (CCs). The RPL of the LiF crystals and the TLD-100 pellets was measured by an Andor iDus 401 CCD camera attached to an Acton Research Spectra Pro 300i monochromator under continuous wave laser excitation at 445 nm, while that of the LiF films was measured by a Nikon Eclipse 80i fluorescence microscope equipped with an Andor NEO sCMOS camera and a blue LED source. The RPL signal intensity of both F2 and F3+ CCs showed a linear behavior as a function of the irradiation dose for all of the three types of LiF-based detectors in the entire dose range. Due to high stability of the CCs at room temperature, the RPL measurements could be repeated without any signal decay; moreover, the detectors can be reused after erasing the CCs by thermal annealing. These results show the possibility of exploiting the RPL of these LiF-based detectors for dosimetry of gamma rays in a very wide dose range. This research was carried out within the CRYPTOMARS project funded by the Italian Space Agency.

Presented author:
Carmen Cecília Bueno - IPEN-CNEN/SP

Authors:
1. Anderson M. B. Silva, Instituto de Pesquisas Energéticas e Nucleares, Brazil 2. Patrícia L. Antônio, Instituto de Pesquisas Energéticas e Nucleares, Brazil 3. Carmen C. Bueno, Instituto de Pesquisas Energéticas e Nucleares, Brazil 4. Divanizia N. Souza, Universidade Federal de Sergipe, Brazil 5. Josemary A.C. Gonçalves, Instituto de Pesquisas Energéticas e Nucleares, Brazil 6. Linda V. E. Caldas, Instituto de Pesquisas Energéticas e Nucleares, Brazil

Crystalline materials exhibit luminescent properties that are valuable for monitoring various physical phenomena, including the dose assessment from ionizing radiation. Optically stimulated luminescence (OSL) and thermoluminescence (TL) have been widely adopted for radiation dosimetry. This study advances research on luminescent dosimetry materials and their practical applications, focusing on lanthanide and metal-doped materials within a CaSO₄ matrix. Novel CaSO₄Ce,Mn phosphors have been synthesized using three distinct methods: solid-state diffusion, precipitation, and slow evaporation. The analysis of pellets produced by incorporating Teflon into the phosphors demonstrated that the synthesis method significantly influences their luminescent properties. The slow evaporation route and solid-state diffusion yielded the highest intensity of TL glow curves, characterized using Schott BG-39 and Hoya U-340 bandpass filters. All synthesis routes showed a single TL peak in the visible region, centered around 155°C. In the ultraviolet region, two peaks were identified for samples produced via the evaporation and solid-state diffusion methods. Regards the precipitation route, a low signal corresponding to the residual signal was found. In the OSL analyses, performed with continuous intensity optical stimulation and a 40-second integration time, all samples exhibited an exponential decrease in OSL signal as the charge traps were emptied. The CaSO₄ phosphor produced via slow evaporation showed the highest OSL intensity, followed by those synthesized through precipitation and solid-state diffusion, all demonstrating low coefficients of variation (CV) in their responses. The higher CV observed in the TL responses of phosphors produced by precipitation and solid-state diffusion, in contrast to the slow evaporation method, indicates a need to optimize production parameters and improve selection criteria. This is essential to ensure measurement accuracy and reproducibility for each dosimeter. Besides the luminescent evaluations of materials with a beta source, their applications in radiation processing dosimetry are also investigated in this work.

Presented author:
Janusz Winiecki - Medical Physics Department of Oncology Center in Bydgoszcz

Authors:
Bogna Sobiech1, Sandra Witkiewicz-Łukaszek2, Yuriy Zorenko1,2, Janusz Winiecki2,3 1Oncology Center, Medical Physics Department, 85-796 Bydgoszcz, Poland 2Physical Faculty of Kazimierz Wielki University, 85-090 Bydgoszcz, Poland 3Collegium Medicum of Nicolaus Copernicus University, 85-067 Bydgoszcz, Poland

Conventional detectors based on ionization chambers, semiconductors or thermoluminescence materials in principle cannot be used for in-situ verification of the dose delivered in brachytherapy procedures with γ-rays sources. The first approach to solve this problem is to use the fiber-optic OSL detectors (FOD) with dosimetric materials that can be located in the patient's body to measure the radiation dose. Meanwhile, the complication of OSL based FOD is the use of two optical pathways in the fiber to stimulate and record OSL light. However, we found that the scintillation properties of materials, such as intensity and emission spectra of radioluminescence can be used also for in-situ dose determination. This method is fast, fully non-invasive and safe. The scintillators with close-to tissue density can be used in any location because they do not interfere with dose distribution. However, there are many radiation therapy types where the detector can be located behind the target. In this case, the use of high-density/high-Zeff scintillators is strongly preferred. In this work, we have developed new scintillation FODs for in situ radiation dose measurements in brachytherapy. The scintillation detectors based on the GAGG:Ce crystal with high density 6.63 g/cm3 and Zeff=54.4 and tissue-equivalent Al2O3:C crystal (ρ=3.95 g/cm3; Zeff=10.2) with 2*2*1mm size were tested. The measurements of applied radiation dose in the 0.05-8 Gy range during brachytherapy treatment with 192Ir source were performed in first in a phantom, and then on the patients in the clinical conditions of the Oncology Center in Bydgoszcz. The obtained first results are very encouraging and demonstrated the large potential of developed FODs for medical application. Investigation on the phantom showed the perfect linear correlation between the delivered dose and scintillation response registered by GAGG:Ce crystal detector. Close to linear dependence between the dose/intensity of scintillation response was obtained also for tissue-equivalent Al2O3:C crystals.

Presented author:
Massimo Piccinini - ENEA C.R. Frascati

Authors:
1. - Massimo Piccinini, ENEA C.R. Frascati, Nuclear Department, Via E. Fermi 45, 00044 Frascati (Rome), Italy 2. - Enrico Nichelatti, ENEA C.R. Casaccia, Nuclear Department, Via Anguillarese 301, 00123 S. Maria di Galeria (Rome), Italy 3. - Maria Aurora Vincenti, ENEA C.R. Frascati, Nuclear Department, Via E. Fermi 45, 00044 Frascati (Rome), Italy 4. - Valentina Nigro, ENEA C.R. Frascati, Nuclear Department, Via E. Fermi 45, 00044 Frascati (Rome), Italy 5. - Rosa Maria Montereali, ENEA C.R. Frascati, Nuclear Department, Via E. Fermi 45, 00044 Frascati (Rome), Italy 6. - Alessandro Ampollini, ENEA C.R. Frascati, Nuclear Department, Via E. Fermi 45, 00044 Frascati (Rome), Italy 7. - Concetta Ronsivalle, ENEA C.R. Frascati, Nuclear Department, Via E. Fermi 45, 00044 Frascati (Rome), Italy

Recently, Fluorescent Nuclear Track Detectors (FNTDs) have been demonstrated in lithium fluoride (LiF) crystals. In the framework of the BIOTRACK project, solid-state detectors based on LiF films were grown by thermal evaporation on Si(100) substrates, with nominal thickness 2 μm, at ENEA Frascati, Italy. They were tested as FNTDs for 1 MeV protons produced by the vertical low-energy extraction line of the TOP-IMPLART proton linear accelerator in operation at ENEA Frascati. The LiF films were irradiated with the film plane parallel to the beam propagation direction and the film edge directly exposed to the incident beam. Keeping the fluence below 10^7 protons/cm^2, it was possible to record single entire proton tracks. Exploiting the red radiophotoluminescence (RPL) of F2 color centers (CCs) created by the protons inside the LiF films, the track images were visualized with a Nikon Eclipse 80i fluorescence microscope. The microscope was equipped with a blue LED for exciting the CC RPL, which was filtered through a Chroma AT515lp filter and detected by an Andor NEO sCMOS camera for image acquisition. Increasing the fluence by two orders of magnitude, the superposition of the very high number of tracks allowed to reconstruct the luminescent Bragg curve of the proton beam. This curve was best fitted using a random-optimization approach, where Bragg curves in LiF are calculated using a smart interpolation of a set of Monte Carlo simulated Bragg curves of monochromatic protons while varying the number of energy bins during the random-optimization cycles to increase the energy spectral resolution. With this method, the energy spectrum of the beam could be estimated, properly taking into account also the type of substrate and the film characteristics.

Presented author:
Matteo Ferrari - CERN/Université Jean Monnet Saint-Etienne

Authors:
Y.Q. Aguiar, Organisation Européenne pour la Recherche Nucléaire, Switzerland and Université Jean Monnet Saint-Etienne, France M. Ferrari, Université Jean Monnet Saint-Etienne, France A. Raj Mandal, Université Jean Monnet Saint-Etienne, France X. Li, Research Neutron Source Heinz Maier-Leibnitz (FRM II), Technical University of Munich, Germany V. Hutanu, Research Neutron Source Heinz Maier-Leibnitz (FRM II), Technical University of Munich, Germany A. Morana, Université Jean Monnet Saint-Etienne, France R. García Alía, Organisation Européenne pour la Recherche Nucléaire, Switzerland S. Girard, Université Jean Monnet Saint-Etienne, France and Institut Universitaire de France (IUF), France

Accurate dosimetry in high-dose mixed radiation fields, such as those encountered in particle accelerators, nuclear reactors, and industrial irradiation facilities, is essential for operational safety and precise radiation monitoring. This study presents a comparative evaluation of dyed-polymethylmethacrylate (PMMA) dosimeters and Radiophotoluminescent (RPL) glass dosimeters under extreme dose and dose rate conditions, with a focus on their sensitivity, and dose rate dependency. The used PMMA dosimeters are the commercially available Harwell Red 4034, whose sensitivity ranges up to 50 kGy. They are widely used in industrial radiation processing to measure high doses of gamma radiation through visible darkening analysed via spectrophotometry, with 640 nm as the recommended wavelength. On the other hand, the RPL dosimeters are commercial cylindrical FD7 glasses supplied by Chiyoda Technol, Japan. Although primarily designed for personal dosimetry, i. e. up to a few Gy, at CERN, their sensitivity is extended up to MGy levels. Recent RPL studies indicate that dose rate effects and deviations from linear response might become significant for high dose levels, starting around 300 kGy. This work investigates the possibility of extending the dose range sensitivity and overall response reliability of PMMA and RPL dosimeters by multi-wavelengthabsorbance measurements in the visible and Near Infrared (NIR) ranges. Irradiation campaigns include gamma radiation and mixed radiation fields, complemented by Monte Carlo simulations using PHITS to understand the energy deposition mechanisms in both materials. Dose rate effects, sensitivity, linearity, and material-specific responses will be analysed in detail. Radiation-induced attenuation (RIA) and photoluminescence signals will further be examined to reveal spectral dependencies across the dosimeters. These findings contribute to advancing dosimetry techniques, enabling more reliable and accurate monitoring in extreme radiation conditions.

Presented author:
Anna Vignati - Università degli Studi di Torino and INFN

Authors:
M. Centis Vignali, Fondazione Bruno Kessler, Center for Sensors and Devices, Trento, Italy R. Cirio, Department of Physics - University of Turin and INFN, Turin, Italy E. Data, Department of Physics - University of Turin and INFN, Turin, Italy S. De Astis, Department of Physics - University of Turin and INFN, Turin, Italy U. Deut, Department of Physics - University of Turin and INFN, Turin, Italy V. Ferrero, Department of Physics - University of Turin and INFN, Turin, Italy A. Ferro, Department of Physics - University of Turin and INFN, Turin, Italy S. Giordanengo, Department of Physics - University of Turin and INFN, Turin, Italy F. Mas Milian, INFN, Turin, Italy and Department of Exact and Technological Sciences, University of Santa Cruz, Ilhéus, Brazil F. Mazinani, INFN, Turin, Italy E. Medina, Department of Physics - University of Turin and INFN, Turin, Italy D.M. Montalvan Olivares, Department of Physics - University of Turin and INFN, Turin, Italy V. Monti, Department of Physics - University of Turin and INFN, Turin, Italy F. Mostardi, Department of Physics - University of Turin and INFN, Turin, Italy G. Paternoster, Fondazione Bruno Kessler, Center for Sensors and Devices, Trento, Italy R. Sacchi, Department of Physics - University of Turin and INFN, Turin, Italy

Introduction. The FRIDA and MIRO INFN projects study the silicon technology for beam monitoring and dosimetry in ultra-high dose-rates regimes (UHDR) and in Spatial Fractionated Radiotherapy (SFRT). The design of 2D segmented configurations of thin silicons in combination with a multichannel front-end readout chip (TERA) aims at exploiting the high spatial resolution and reducing the dose and stray radiation of point measurements. Materials and Methods. The response linearity of PiN pads (30 and 45 μm active thickness, from 0.25 to 2 mm2 areas) was tested with 9 MeV electron FLASH beams (CPFR, Pisa, Italy) at increasing dose-per-pulse, using both an oscilloscope and the TERA chip, a current-to-frequency converter. A strip detector (2.6×2.6 cm2, 60 µm thickness) was tested at conventional dose-rates with proton beams (CNAO, Pavia, Italy) and with 10 MeV electron beams using a PMMA applicator and a tungsten grid collimator (7×7 array of 1mm2 square holes, 3 mm center-to-center distance), reading out 128 strips out of the 144 available with two 64-channel TERA chips. Results. When polarizing the sensors at 200 V and splitting the pad signal into the 64 TERA channels, a response linearity of PiN pads was found beyond 10 Gy/pulse, and the capability to measure the time structure of beam pulses. The FWHM values of the proton beams of CNAO (62.28 - 226.91 MeV energy, 5×108 protons per spill) were accurately measured by the strip silicon sensor. The measurements performed with 10 MeV electron beams passing through the tungsten collimator resulted in a center-to-center distance of 3.02±0.02 mm and 1.17±0.06 mm peaks FWHM. Conclusions. The response linearity of silicon sensors in UHDR regimes and their beam shape capability with proton beams and with conventional and spatially fractionated electron were preliminary demonstrated. Further studies of the sensor and readout chip are ongoing.

Presented author:
Sergii Ubizskii - Lviv Polytechnic National University

Authors:
1.– Sergii Ubizskii, Lviv Polytechnic National University, Lviv, Ukraine 2.– Yaroslav Zhydachevskyy, Institute of Physics, Polish Academy of Sciences, Warsaw, Poland 3.– Oleksandr Poshyvak, Lviv Polytechnic National University, Lviv, Ukraine 4.– Zuzanna Pawlowska, Central Laboratory for Radiological Protection (CLOR), Warsaw, Poland 5.– Elena Bakhanova, National Research Center for Radiation Medicine, Hematology and Oncology of National Academy of Medical Sciences of Ukraine; RPE Dosimetrica, Kyiv, Ukraine 6.– Vadim Chumak, National Research Center for Radiation Medicine, Hematology and Oncology of National Academy of Medical Sciences of Ukraine; RPE Dosimetrica, Kyiv, Ukraine

The idea of determining the quality of X-ray radiation by measuring the absorption dose of two phosphors with different effective atomic numbers Zeff was proposed more than 60 years ago [1]. However, a reliable distinction of radiation energy requires a significant difference in the atomic numbers of the phosphors used. On the other hand, it was generally believed that phosphors suitable for passive luminescent dosimetry should be tissue-equivalent, i.e. have a sufficiently low Zeff close to about 7.5, and there was a lack of the well-studied high-Z storage phosphors for dosimetry. The present work is devoted to analysis of this old idea and its implementation for needs of urgent emergency dosimetry for rapid assessment of unknown radioisotope radiation energy. The last can occur in case of terrorist attack with use of so called dirty bomb. Our approach is based on use of BeO-based phosphor (Zeff = 7.1) which is almost tissue equivalent and the high-Z phosphor based on YAlO3 (Zeff = 31.4). Both phosphors are mounted in one dosimeter casing and were irradiated to the same radiation flux. The measured absorbed dose values are estimated from optically stimulated luminescence (OSL) response using special OSL dosimetric reader developed for this purpose. Because the absorption of radiation flux is strongly dependent on quanta energy the measured values become different and its ratio serves as a measure of radiation quanta energy and a basis for its distinguishing. The concept was experimentally tested for various radiation sources and dose magnitudes. Our results also indicate its suitability for distinguishing the quality of X-ray radiation by means of dose measurement. [1] G.N. Kenney, J.R. Cameron, X-ray Beam Quality Measurements Utilizing TL Dosimeters, Technical Report No. TID-19112., U.S.A. 1963 (https://www.osti.gov/biblio/4679893).

Presented author:
Alexander Romanyukha - Armed Forces Radiobiology Research Institute

Authors:
J.L. Saunders, Naval Dosimetry Center, Bethesda, MD, USA A. Smolinski, Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, MD, USA K. Riley, Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, MD, USA A. Guynn, Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, MD, USA A. Tsioplaya, Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, MD, USA A. Cook, Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, MD, USA

Alanine Electron Paramagnetic Resonance (EPR) dosimetry is capable of measuring the total (neutron + photon) dose of a neutron source. There are also commercially available optically stimulated luminescence (OSL) dosimeters and readers that can accurately measure photon doses. Independent measurement of the photon dose contribution is important because alanine has a different sensitivity to neutrons and photons when calibrating in terms of tissue kerma from 60Co gamma radiation. Therefore, OSL dosimetry can be used to separate neutron and photon dose contributions of the total dose measured by alanine. Armed Forces Radiobiology Research Institute (AFRRI) research reactor produces various neutron-photon mixtures used mostly for radiobiological experiments. Many phantoms at the AFRRI are used to measure the accuracy of dose delivery in animal experiments. In the present work standard and 3D printed rat phantoms with equipped with OSL and alanine dosimeters were used. A special holder capable to hold four alanine pellets and four OSL NanoDot dosimeters was designed and 3D printed. During irradiation this holder was inserted into the rat phantoms. The results of neutron and photon dose measurements after irradiation to different photon and neutron mixtures will be presented. Based on these dose measurements the difference in sensitivity of alanine to the neutron and photon was determined. Alanine neutron dose measurements were validated using other dosimetry techniques. Further applications of the developed approach are discussed. The opinions, conclusions, and recommendations herein expressed are those of the authors and do not necessarily reflect the official policy or position of the Uniformed Services University or the Department of Defense.

Presented author:
Malgorzata Magdalena Kasprzak - Paul Scherrer Insitute

Authors:
1. Malgorzata Magdalena Kasprzak, Paul Scherrer Institute, Department of Radiation Safety and Security, Switzerland 2. Marco Caresana, Politecnico di Milano (PoliMi), Italy 3. Mirco Dietz, Physikalisch-Technische Bundesanstalt (PTB), Germany 4. Sabine Mayer, Paul Scherrer Institute, Department of Radiation Safety and Security, Switzerland 5. Liviu-Cristian Mihailescu, SCK CEN, Belgian Nuclear Research Centre, Belgium 6. Rick Tanner, United Kingdom Health Security Agency, UK 7. Francois Trompier, Institute for Radiological Protection and Nuclear Safety (IRSN) - Laboratoire de dosimétrie des rayonnements ionisants, France

Accurate calibration of neutron dosimeters and dose rate meters is essential for consistent and reliable radiation measurements. Neutron calibration laboratories that provide well-characterized neutron reference fields according to the ISO-8529 standard often encounter challenges related to the contribution of backscattered neutrons, among other factors. This is problematic since the response of neutron dose rate monitors and personal dosimeters strongly depends on neutron energy and direction. Although there are various calculation and measurement methods to correct for this, there are still few studies comparing calibrations between different neutron calibration laboratories, especially those not included in the BIMP CCRI(III) comparisons. To address this issue, EURADOS has taken the initiative to launch a survey among neutron calibration laboratories to collect information on current practices and methodologies, with a specific focus on the need for intercomparison exercises. This presentation shows the results of the survey, which covered key aspects such as the size and characteristics of calibration rooms, with a particular emphasis on the contribution of backscattered neutrons and the methods used to quantify this component. Respondents provided details on typical calibration distances and the types of neutron reference fields used, such as those produced by 241Am-Be and 252Cf sources. Additionally, the survey gathered information on the quantities reported by the laboratories and the traceability chains. The findings provide valuable insights into the common practices and challenges faced by laboratories and emphasize the need for future intercomparison exercises to maintain uniform standards and improve the reliability of calibration procedures. This work will discuss the trends observed, address discrepancies, and outline the steps needed to promote collaboration in the field of neutron metrology.

Presented author:
Gerardo Antonio Noguera Vega - Universidad de Costa Rica

Authors:
1.-G.Noguera V, Universidad de Costa Rica, Costa Rica

Dosimetry is essential for ensuring the safety of workers and patients exposed to ionizing radiation. Traditionally, a single calibration factor is used to account for a wide range of energies in various applications, such as medical imaging and industrial settings. However, this generalized approach may not effectively capture the nuances of specific radiological practices and energy levels, leading to inaccurate dose measurements. This study examines the impact of using practice-specific calibration factors compared to a single generalized factor. It considers various radiation practices, including mammography, computed tomography (CT), conventional radiology, radiotherapy,industrial radiography and nuclear medicine, each with distinct energy ranges. The results highlight significant improvements in accuracy when practice-specific and energy-specific calibration factors are used. The findings reveal that tailored calibration factors can improve dose measurement precision by up to 12% for low-energy applications, with a range of 8%-12% for conventional radiology. For CT energies and Nuclear medicine, accuracy improves by 5%-10%, while cesium-137 reference energies show no significant difference. Higher energy applications, such as those involving cobalt-60, also demonstrate improvement with specific calibration factors. In conclusions these results remarks that refining calibration factors according to the energy range and practice can enhance dosimetry, providing more accurate evaluations of radiation exposure and improving safety in both medical and industrial applications. References:International Commission on Radiological Protection (ICRP). (2007). ICRP Publication 103: The 2007 Recommendations of the International Commission on Radiological Protection. Annals of the ICRP, 37(2-4). International Commission on Radiation Units and Measurements (ICRU). (1995). ICRU Report 95: Quantities and Units in Radiation Protection Dosimetry. ICRU Publications. Brenner, D. J., & Hall, E. J. (2007). Computed Tomography—An Increasing Source of Radiation Exposure. The New England Journal of Medicine, 357(22), 2277-2284. https://doi.org/10.1056/NEJMra072149 National Council on Radiation Protection and Measurements. (2004). NCRP Report No. 160: Ionizing Radiation Exposure of the USA Population.NCRP.

Presented author:
Tamás Pazmandi - HUN-REN Centre for Energy Research

Authors:
Dorottya Jakab, HUN-REN Centre for Energy Research, Hungary András Kocsonya, HUN-REN Centre for Energy Research, Hungary Anna Pántya, HUN-REN Centre for Energy Research, Hungary Zsófia Rékasi, HUN-REN Centre for Energy Research, Hungary Csilla Rudas, HUN-REN Centre for Energy Research, Hungary Márton Zagyvai, HUN-REN Centre for Energy Research, Hungary

Decades of experience and expertise at the Centre for Energy Research in Hungary in internal and external dosimetry, including neutron measurements from the operational experiences of the Budapest Research Reactor and other experimental facilities, have laid the groundwork for advancing neutron dosimetry practices. A few years ago, a new project aimed at improving the personal neutron dosimetry system was launched with support from the IAEA technical cooperation programme. Developing reliable methods for personal neutron dosimetry poses a significant challenge as there is no standardized approach and a universally applicable method for all measurement conditions. The primary objective of the project was to enhance our neutron dosimetry programme to ensure effective radiation protection for workers exposed to neutron radiation due to the use of radiation sources and the application of nuclear technologies. Meeting the special personal neutron dosimetry needs arising from unusual circumstances in the expanding range of new activities and with the establishment of new facilities planned in Hungary were also considered. The project comprises of the following actions: • a detailed condition assessment of the existing system to serve as the basis for further development, • development and implementation of methodologies for personal neutron dosimetry, guided by the relevant standards, guides and recommendations, as well as the latest research findings, • examination of international good practices, • establishment of a state-of-the-art dosimetry laboratory by upgrading the existing infrastructure and installing the necessary instrumentation to build capacity to handle the operation of neutron dosimetry service, • establishing and training of a competent staff to maintain the appropriate and efficient operation. The outcomes of the project, including the system components and procedures, and the key lessons learned during implementation will be presented in detail.

Presented author:
FRANCESCO D'ERRICO - Università di Pisa

Authors:
Francesco d’Errico, Scuola di Ingegneria, Università di Pisa, Pisa, Italy — Susana de Souza Lalic, Departamento de Física, Universidade Federal de Sergipe, São Cristóvão-SE, Brazil — Linda Caldas, Instituto de Pesquisas Energéticas e Nucleares, São Paulo-SP, Brazil — Gianpaolo Roina, Scuola di Ingegneria, Università di Pisa, Pisa, Italy — Andrea Chierici, Scuola di Ingegneria, Università di Pisa, Pisa, Italy — Riccardo Ciolini, Scuola di Ingegneria, Università di Pisa, Pisa, Italy

This study aims to overcome the energy dependence of conventional albedo dosimetry and address challenges in mixed radiation fields. By advancing the detection capabilities for fast neutrons, the proposed system holds potential for significant improvements in personal neutron dosimetry, enhancing radiation safety practices across diverse applications. Albedo neutron dosimetry is widely recognized for its advantages, including high sensitivity to low-energy neutrons, isotropic response, ease of use, and cost-effectiveness. These characteristics make it particularly suitable for monitoring slow-neutron-dominant environments, such as near shielded nuclear reactors. However, albedo dosimetry faces limitations, particularly in detecting fast neutrons, where energy dependence reduces its accuracy. Current methods often require complex calibration processes and encounter challenges in mixed radiation fields, where distinguishing neutron from gamma contributions can lead to overestimations of neutron dose. This research aims to address these limitations through an innovative approach employing dual albedo dosimeter badges. By enhancing response to fast neutrons, the proposed system improves the accuracy of personal equivalent dose measurements while retaining the inherent benefits of albedo dosimetry. The methodology is detector-independent, functioning with any albedo-mode material, thereby offering flexibility and broad applicability. The research integrates Monte Carlo simulations and experimental validations. Simulations refine the design and assess performance under various neutron energy spectra, while experimental tests are conducted using a BOMAB-type phantom and IPEN’s irradiation facilities. These include a cesium gamma-ray source, an AmBe neutron source, and the thermal neutron beam from the IEA-R1 nuclear research reactor.

Presented author:
Gerardo Antonio Noguera Vega - Universidad de Costa Rica

Authors:
1.-G.Noguera V,CICANUM-Universidad de Costa Rica, Costa Rica

Implementing ICRU-95 presents significant challenges, including the need for advanced dosimeter designs with greater sensitivity and precision. Standardization becomes complex when adapting calibration setups to diverse radiation beams, SSDs, and phantoms. Achieving regulatory alignment across institutions and updating quality assurance protocols require substantial effort and investment, with uncertain long-term benefits. Adopting ICRU-95 recommendations has significantly impacted personal dosimetry by enhancing dose measurement accuracy, crucial for radiation safety in medical and industrial settings. This study analyzes dosimeter responses across energy ranges, comparing traditional quantities like Hp(10) with those based on ICRU-95 recommendations. In the low-energy range (below 50 keV), traditional dosimeters often overestimate doses by up to 30% due to stronger attenuation and scattering effects, but ICRU-95 factors reduce this discrepancy to about 10%. For medium energies (50-150 keV), overestimation differences narrow to 10-15%, enhancing reliability in diagnostic radiology. At higher energies (150-300 keV), discrepancies decrease to around 5-8%, crucial for radiation therapy and high-energy imaging. Above 300 keV, dosimeter accuracy improves, with traditional and ICRU-95 factors yielding similar results. For very high energies (above 1 MeV), traditional dosimeters tend to underestimate doses by 15%, but ICRU-95 factors reduce this to less than 5%. In conclusion, new calibration factors according to ICRU-95 could improve personal dosimetry, accuracy, and precision across different energy ranges. However, challenges remain, including the investment required for implementation. Despite this, the potential benefits in individual health monitoring are not yet clear enough to justify the implementation. References: ICRU Report 95: Key Recommendations for Dosimetry of Ionizing Radiation. International Commission on Radiation Units and Measurements. The Impact of New Dosimetric Quantities in Radiation Protection. Radiation Protection Dosimetry, 198(4), 311-318. https://doi.org/10.1093/rpd/ncac150. Jones, D. R., & Silverman, R. (2022). Implications of ICRU-95 Guidelines on Dosimetry and Radiation Protection. Journal of the IAEA, 64(5), 42-51. https://doi.org/10.1016/j.jradiol.2022.08.003.

Presented author:
Julio César Reyes De León - Unidad Académica de Física, Universidad Autónoma de Zacatecas

Authors:
Reyes De León J. C. 1, Pérez Arrieta M. L. 1, Torres Cortés C. O. 1 1) Unidad Académica de Física, Universidad Autónoma de Zacatecas, Avenida solidaridad, Col. Hidráulica 98068, Zacatecas, México.

In this work we studied the thermoluminescent (TL) properties of magnesium tetraborate doped with dysprosium (MgB₄O₇: Dy), a material known for its tissue equivalence and significant potential in radiation dosimetry, particularly in medical and environmental applications. MgB₄O₇: Dy was synthesized using two distinct methods: solid-state synthesis and hydrothermal synthesis. The aim was to explore its capability to produce particles with reduced sizes, ideally at the nanoscale, and to evaluate how these variations in particle size influence the material's TL performance. The main focus of this research is to compare the TL properties of materials synthesized by both methods under X-ray irradiation. The investigation emphasizes the relationship between particle size and key dosimetric parameters such as the intensity of TL emission peaks, the linearity of the dose-response, and the temporal stability of TL signals. These characteristics are crucial for optimizing the performance of the material in practical dosimetric applications. Additionally, the study assesses how the synthesis method influences structural properties, including particle size uniformity and the distribution of crystal defects introduced during dysprosium doping. These factors are critical in determining the efficiency of energy trapping and subsequent release processes, which underpin the material's TL behavior. The reproducibility of TL signals and their resistance to fading are also analyzed, as these aspects are fundamental for reliable dosimetry. Preliminary findings indicate that the choice of synthesis route and control over particle size are pivotal in enhancing the TL properties of MgB₄O₇: Dy. This opens up opportunities to design more sensitive, stable, and versatile TL materials. By establishing the link between structural and optical properties and dosimetric performance, this study contributes to the advancement of materials for accurate radiation dose measurements, fostering innovation in medical and environmental monitoring technologies.

Presented author:
Erick Campa Velázquez - UAZ

Authors:
Erick Campa Velázquez, UAZ, México Ana Valeria Flores Esparza, UAZ, México María Leticia Pérez Arrieta, UAZ, México Carina Oliva Torres Cortés, UAZ, México

Ionizing radiation is of great importance in the study of materials, which is why an X-ray emitter was developed to meet the current scientific needs of the study of materials. This includes being more compact and cost-efficient, as well as guaranteeing the quality of the emitted rays and complying with international radiation safety standards. This development included the use of high precision and high quality components to ensure the consistency of the system and minimize the potential risks associated with radiation exposure. To protect operators and the environment, detailed calculations were made of the necessary shielding, selecting materials such as lead and concrete for their radiation attenuation properties. These specifications were validated through simulations and experimental tests, ensuring their practical effectiveness. The design of the machine included an X-ray tube with a copper target and an acceleration voltage of between 30 kV and 40 kV, accompanied by an advanced control system that allowed significantly reducing the number of photons emitted by the tube. In addition, advanced real time monitoring systems were implemented, such as a Geiger counter, which guaranteed continuous control of radiation exposure, ensuring adequate operating conditions. An operation and maintenance manual was also prepared, which included specific procedures for calibration, safe use and preventive maintenance of the machine. This document sought to standardize the handling of the equipment, prolong its useful life and avoid possible operational failures. The development of this emitter represented a significant advance in X-ray technology, providing a versatile and reliable tool for materials research. Its implementation allowed laboratory tests to be carried out on synthesized materials for the purpose of evaluating them as potential dosimeters. The objective of this work was to build and calculate the primary shielding of an experimental X-ray source, facilitating the characterization of materials and thus optimizing their scientific development.

Presented author:
Liang Zhao - Kyoto University

Authors:
Liang Zhao 1,2 , Nishiki Matsubayashi 1 , Naonori Hu 1,3 , Takushi Takata 1 , Akihiro Yamaji 4 , Shunsuke Kurosawa 4 , Hiroki Tanaka 1 1 Institute for Integrated Radiation and Nuclear Science, Kyoto University, 2-1010 Asashironishi, Kumatori, Osaka, 590-0494, Japan 2 Graduate School of Engineering, Kyoto University, Katsura, Kyoto Nishikyo-ku, Kyoto, 615-8246, Japan 3 Kansai BNCT Medical Center, Osaka Medical and Pharmaceutical University, 2-7 Daigaku-Machi, Takatsuki City, Osaka, Japan 4 Institute for Materials Research, Tohoku University, 2-1-1, Katahira, Aoba-ku, Sendai Miyagi 980-8577, Japan

Boron Neutron Capture Therapy (BNCT) is a type of radiation therapy that selectively damages tumor cells through nuclear reactions between thermal neutrons and 10 B atoms accumulated in cancer cells. From the perspective of evaluating patient safety, it is desirable to measure the neutron ambient dose outside the irradiation field, and a detector suitable for BNCT irradiation fields is required. To enable measurement of the newly proposed operational quantity, neutron ambient dose H*, a structural assembly composed of polyethylene, tungsten, and gadolinium was designed around the thermal neutron detector to optimize its response in accordance with the conversion coefficients, h*, defined in ICRP116. An Eu-doped LiCaAlF 6 (LiCAF) scintillator was selected as the thermal neutron detector. This structural assembly of the neutron ambient detector reduces the thermal neutron flux reaching the LiCAF scintillator. A relatively larger LiCAF scintillator was required to reduce the time of measurement. However, the size could not be excessively large considering gamma ray event suppression. In this study, three relatively large LiCAF crystals were prepared: (i) a 2 mm cube, (ii) a 2 mm diameter × 1 mm thick disk, and (iii) a 2 mm diameter × 0.5 mm thick disk. Each was coupled with a 3 mm diameter light guide and irradiated in the E-3 neutron guide tube of the Kyoto University Reactor (KUR). Among the samples, the 2 mm diameter × 0.5 mm thick disk (iii) exhibited the best gamma-ray suppression. Therefore, this configuration was adopted in the design of the neutron ambient dose detector. The total measurement time was estimated to be 57 minutes, which is considered practical for actual applications. In the future, we plan to create a neutron ambient detector using the LiCAF scintillator optimized in this study and adapt it to the irradiation field.

Presented author:
Rafał PORZEZIŃSKI - Institute of Physics, Jan Dlugosz University

Authors:
Rafał PORZEZIŃSKI and Arkadiusz MANDOWSKI

Thermoluminescence (TL) and Optically Stimulated Luminescence (OSL) are widely used for radiation dosimetry and dating. The kinetics of charge carrier trapping and recombination underlying these processes is complex. While classical models like the Simple Trap Model (STM) and the Localized Transition (LT) model exist, they often fail to fully explain experimental observations. The Semi-Localized Transition (SLT) model, proposed by Mandowski in 2005, offers a more comprehensive framework by incorporating both localized recombination within trap-recombination center (T-RC) pairs and delocalized transitions via transport bands. SLT successfully accounts for phenomena like displacement peaks and anomalously high frequency factors. Despite its advantages, the mathematical complexity of the SLT model, described by a system of 7 differential equations, hinders its direct application for analyzing experimental data and estimating crucial physical parameters. Finding reliable analytical approximations is essential to simplify the model and enhance its practical utility. The quasi-equilibrium (QE) approximation may be a useful tool to achieve such simplification. This work investigates the applicability and validity of QE approximations within the SLT framework. It is focused on the conditions under which the QE assumptions hold true. Its validity is verified by solving the full set of SLT kinetic equations using specialized algorithms suitable for stiff differential systems, such as Radau methods implemented in Python. The goal is to derive and test simplified analytical models based on QE conditions. We explore the behavior of these approximations under various physical conditions, including different trap parameters, heating rates, comparing their predictions against the full numerical solutions of the SLT model. The development of validated QE approximations for SLT would provide simpler, yet physically grounded, tools for interpreting TL and OSL experimental results, potentially leading to more accurate parameter estimation and a better understanding of luminescence kinetics in diverse materials.

Presented author:
Lily Bossin - Paul Scherrer Institute

Authors:
1. Lily Bossin, Department of Radiation Safety and Security, Paul Scherrer Institute, Switzerland 2. Daniel Zeitz, Department of Radiation Safety and Security, Paul Scherrer Institute, Switzerland 3. Jeppe B. Christensen, Department of Radiation Safety and Security, Paul Scherrer Institute, Switzerland 4. Federico Geser, Department of Radiation Safety and Security, Paul Scherrer Institute, Switzerland 5. Eike Hohmann, Department of Radiation Safety and Security, Paul Scherrer Institute, Switzerland 6. Malgorzata Kasprzak, Department of Radiation Safety and Security, Paul Scherrer Institute, Switzerland 7. Malgorzata Sliz, Department of Radiation Safety and Security, Paul Scherrer Institute, Switzerland 8. Alberto Stabilini, Department of Radiation Safety and Security, Paul Scherrer Institute, Switzerland 9. Eduardo G. Yukihara, Department of Radiation Safety and Security, Paul Scherrer Institute, Switzerland 10. Sabine Mayer, Department of Radiation Safety and Security, Paul Scherrer Institute, Switzerland

The need for reliable neutron dosimetry in environmental settings necessitates the use of passive detection systems. Most systems rely on 6LiF thermoluminescence detectors (TLDs) which, despite their high sensitivity to neutrons, are also sensitive to photons and therefore require the subtraction of the photon component. In this work we explore PADC detectors coupled with a thermal neutron converter (6LiF chip) as an alternative to TLDs. Once placed in a moderating sphere, the 6LiF converter generates charged particles through the neutron capture reaction with thermal neutrons, creating tracks in the PADC. The PADC system with a thermal neutron converter was compared to other methods for passive neutron environmental dosimetry, including fission track detectors, stand-alone TLDs, and optically stimulated luminescence detectors (OSLDs). All detectors were exposed to an AmBe neutron field and their performances in terms of dose response, detection limit and precision were assessed. The PADC system demonstrated comparable detection limits to fission track detectors, with H*(10) = 6 µSv vs. H*(10) = 1 µSv, respectively. Furthermore, as gamma-sensitive detectors required additional corrections to account for the photon component, this reduced their overall precision and increased detection limits in mixed radiation fields. In contrast, track-based systems, such as PADC and fission track detectors, proved advantageous due to their insensitivity to photons. However, the saturation of PADCs and fission tracks at higher doses (in the order of mSv) limited their usability in high-dose environments, where luminescence-based detectors offered a broader range of detection. Overall, the proposed PADC system showed potential as a robust alternative for neutron environmental dosimetry, particularly in low-dose scenarios. Further optimisation, such as using alternative converters and etching procedures, could improve its performance and extend its applicability to a higher dose range.

Poster session at the Amoxcalli Lobby - Facultad de Ciencias, UNAM
María de los Angeles Montes Rodríguez - ESFM-IPN The Imparted Energy : its Spatial Dependence in Terms of the Mesoscopic volume
STEEPHENRAJ AROKIYASAMY - Rhodes University On the thermoluminescence and DFT first principles study of the role of point defects in monolayer beryllium oxide
Juan Mittani - UNIFESP OSL response of Al₂O₃ under 405 nm light stimulation
Devesh R. Mishra - Bhabha Atomic Research Center Mumbai INDIA Development of new theoretical and experimental method for the multiple dose assessment without erasing α- Al2O3:C -OSL phosphor
Iván D. Muñoz - German Cancer Research Center Characterization of lithium fluoride fluorescent nuclear track detectors for linear energy transfer measurements in light-ion beams using confocal microscopy
José Fernando Diniz Chubaci - Universidade de São Paulo Development of a Miniaturized Neutron Sandwich Spectrometer Using Advanced BN/SiC Semiconductor Technology
Seungwoo Park - Korea Institute of Radiological & Medical Sciences Characterization of Gafchromic EBT3 Film for Performance evaluation of 2 MeV Irradiation Equipment
Veeraraghavan Akshay Krishnan - Technical University of Denmark Development of a wireless field gamma spectrometer for dose rate determination in the field
María Gil-Tolano - Universidad de Sonora Thermoluminescence dosimetry characterization of HPHT microcrystals diamond exposed to X-Ray
Massimo Piccinini - ENEA C.R. Frascati Radiophotoluminescence response of color centers in lithium fluoride crystals, thin films and TLD-100 pellets for gamma-ray dosimetry
Carmen Cecília Bueno - IPEN-CNEN/SP ASSESSING DOSIMETRIC PROPERTIES OF CaSO4:Ce,Mn PHOSPHORS SYNTHESIZED BY DIFFERENT TECHNIQUES: FROM BETA IRRADIATION TO RADIATION PROCESSING DOSIMETRY
Janusz Winiecki - Medical Physics Department of Oncology Center in Bydgoszcz Real-in-time dose measurements in brachytherapy procedure using scintillation detectors
Massimo Piccinini - ENEA C.R. Frascati Characterization of low-energy protons by fluorescent nuclear track detectors based on lithium fluoride films on silicon substrates
Fang-Yuh Hsu - National Tsing Hua University Development and verification of dose algorithm for the new OSL eye-lens dosimeter
Matteo Ferrari - CERN/Université Jean Monnet Saint-Etienne Response comparison of FD-7 radiophotoluminescence (RPL) glass dosimeters and dyed-polymethylmethacrylate (PMMA) dosimeters at high dose levels
Anna Vignati - Università degli Studi di Torino and INFN SILICON SENSORS FOR MONITORING FLASH AND SPATIALLY FRACTIONATED BEAMS
Sergii Ubizskii - Lviv Polytechnic National University The concept of distinguishing radiation energy based on the measurement of absorbed doses and its implementation using a pair of phosphors with high and low atomic number
Satoshi Kodaira - National Institutes for Quantum Science and Technology On-site space radiation dosimeter for deep space missions
Alireza Talebitaher - CNL Harmonized Phantom Performance for Shallow Dose and Eye-Lens Beta Irradiation
Alexander Romanyukha - Armed Forces Radiobiology Research Institute Application of combined EPR alanine/OSL Al2O3:C dosimetry for neutron and photon dose measurements
Yu-Tien Tsai - National Atomic Research Institute (NARI) Regional Investigation on Reference Dosimetry Using Calibration in Co-60 and Megavoltage Photon Beams in Taiwan
Malgorzata Magdalena Kasprzak - Paul Scherrer Insitute Results of the survey for the EURADOS intercomparison of neutron calibration laboratories: Harmonization advancement in neutron metrology
Nancy Umisedo - USP Angular dependence of thermally assisted optically stimulated luminescence response of fluorite-based pellets
Gerardo Antonio Noguera Vega - Universidad de Costa Rica Optimizing Dosimetry: Impact of Specific vs. General Calibration Factors Across Energy Ranges and practices
Tamás Pazmandi - HUN-REN Centre for Energy Research Improvement of the personal neutron dosimetry system in Hungary
FRANCESCO D'ERRICO - Università di Pisa Advancing Albedo Neutron Dosimetry for Enhanced Fast Neutron Detection
Gerardo Antonio Noguera Vega - Universidad de Costa Rica Implications of Implementing ICRU-95 in Personal Dosimetry: Impact on Calibration Factors Based on Energy
Julio César Reyes De León - Unidad Académica de Física, Universidad Autónoma de Zacatecas Effect of Particle Size on the Thermoluminescent Properties of MgB₄O₇: Dy
David Alonso Dueñas Osuna - Universidad de Sonora TL and OSL properties of nanodiamonds
Erick Campa Velázquez - UAZ Construction and calculation of the primary shielding of an experimental X-Ray source
Claudia Isabel Morales Peña - Universidad Autónoma del Estado de México,UAEMéx Bleaching of optically stimulated luminescent dosimeters by different light sources, for clinical dosimetry applications
Liang Zhao - Kyoto University Study on the Optimal Size of the LiCAF Scintillator for Neutron Ambient Dose Detector in BNCT
Rafał PORZEZIŃSKI - Institute of Physics, Jan Dlugosz University Simplified equations for the semi-localized transitions (SLT) model
Lily Bossin - Paul Scherrer Institute Weighing options for passive environmental neutron dosimetry: A comparative study of PADCs, TLDs, OSLDs, and fission track detectors

Tuesday June 10, 2025

Presented author:
Peter Balling - Aarhus University

Authors:
Mads L. Jensen, Dept. of Physics and Astronomy, Aarhus University, Denmark Camilla L Nielsen, Dept. of Physics and Astronomy, Aarhus University, Denmark Morten B. Jensen, Dept. of Medical Physics, Aarhus University Hospital, Denmark. Ludvig P. Muren, Danish Centre for Particle Therapy, Aarhus University Hospital; Dept. of Clinical Medicine, Aarhus University, Denmark Rosana M. Turtos, Dept. of Physics and Astronomy, Aarhus University, Denmark Brian Julsgaard, Dept. of Physics and Astronomy, Aarhus University, Denmark Peter Balling, Dept. of Physics and Astronomy, Aarhus University, Denmark

Spatially resolved readout of optically stimulated luminescence (OSL) from dosimeters of a clinically relevant size has been suggested as an attractive method for three-dimensional (3D) dosimetry. Such capabilities can have a strong impact in radiotherapy research, as the development of new treatment modalities would benefit significantly from access to a radio-physical technique for 3D dosimetry. The approach holds promise to inherit the attractive properties of OSL dosimetry, including high dose precision and reusability. However, clinical applications of 3D OSL-based dosimetry have so far been hampered by the restriction that the 3D dose mapping was demonstrated in large-volume scintillating crystals that also exhibit OSL. These crystals are far from being tissue equivalent, which means that they measure a dose distribution, which is severely distorted relative to the original clinically defined treatment plan. In this contribution, we demonstrate a novel, reusable OSL-based 3D dosimeter material with good tissue equivalence, which can register a radiotherapy dose with high spatial and dose precision. The material consists of a hydrogel matrix containing copper-doped lithium fluoride nanoparticles that are OSL active. Cubic dosimeters measuring 50x50x50 mm^3 are developed and used to measure 3D dose distributions from photon irradiations (in voxels of 0.8x0.8x1.0 mm^3) with a statistical dose precision of 5 % at 100 Gy dose. The tissue equivalence of the dosimeter means that it can go through the entire clinical treatment chain of x-ray CT scan, dose prescription, cone-beam CT alignment on the treatment couch, and treatment delivery. The spatial precision, determined from offsets between steep dose gradients in the treatment plan and the measured dose, is better than the voxel size. In the contribution, we will describe that the properties of the new material are currently limited by light scattering from the embedded nanoparticles and discuss possible future improvements and potential clinical applications.

Presented author:
Go Okada - Kanazawa Institute of Technology

Authors:
1. Go Okada, Kanazawa Institute of Technology, Japan 2. Masanori Koshimizu, Shizuoka University, Japan 3. Wataru Kada, Tohoku University, Japan 4. Kenichi Watanabe, Kyushu University, Japan 5. Kiyomitsu Shinsho, Tokyo Metropolitan University, Japan 6. Yasuhiro Koguchi, Chiyoda Technol, Japan 7. Hidehito Nanto, Kanazawa Institute of Technology, Japan

Radiophotoluminescence (RPL) has garnered significant attention in the field of luminescence dosimetry due to its utility in radiation detection. RPL is defined as a phenomenon in which luminescence centres are generated through interactions with ionizing radiation. These centers, detected by conventional photoluminescence techniques, exhibit an intensity directly proportional to the accumulated radiation dose, thus enabling the quantification of radiation exposure. Therefore, RPL can be used to measure radiation dose. The most successful RPL material for personnel dosimeters is Ag-doped phosphate glass. This material exhibits RPL through the trapping of radiation-generated electrons and holes by Ag+ centres. As a result, an Ag0 centre forms when an electron is trapped while Ag2+ centre emerges when a hole is captured. These centres act as luminescence centre, where photoemission occurs following optical excitation. In particular, the Ag2+ centre exhibits a bright signal, making it a valuable probe for radiation dosimetry. However, the stabilization of its concentration does not occur immediately after irradiation, resulting in short-time instability in the RPL signal limits the use of Ag-doped phosphate glass in real-time dosimetry. Real-time dosimetry is increasingly important in fields such as radiation therapy and nuclear science. Although scintillation detectors are among the primary tools for this purpose, accurate measurements in high-dose fields are challenging due to factors such as Cherenkov radiation, signal pileup, and interference from fluorescence unrelated to scintillation. RPL has potential as an alternative as, in principle, it may allow for noise separation through lock-in-amplification technology. In this research, we conducted a systematic investigation aimed at identifying new RPL materials exhibiting stable signal immediately after dose. Furthermore, we have developed a prototype system for a real-time dosimetry using RPL.

Presented author:
Ilia Filipev - University of Wollongong

Authors:
A. Bashiri(a,b), M. J. Large(a), M. J. Griﬃth(c), L. Papale (d), B. Philippa (d), C. Hall (e), D. Bolst (a), S. Guatelli (a), M. L. F. Lerch (a), A. Rosenfeld (a), A. J. Mozer (f), Marco Petasecca (a), and Jessie A. Posar(a) a. Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW 2522, Australia b. Physics Department, Faculty of Science and Arts, Najran University, Najran 66462, Saudi Arabia c. Future Industries Institute, University of South Australia, Mawson Lakes, SA 5095, Australia d. College of Science and Engineering, James Cook University, Townsville, QLD 4811, Australia e. Imaging and Medical Beamline, Australian Synchrotron, Clayton, VIC 3168, Australia f. Intelligent Polymer Research Institute, University of Wollongong, Wollongong, NSW 2522, Australia

Organic semiconductor-based sensors offer a unique approach to wearable x-ray detection due to their solution processability and carbon-based composition. We have developed a flexible, thin (260 nm) x-ray sensor using an organic bulk-heterojunction P3HT:o-IDTBR active layer with Indium-Tin-Oxide and Aluniumium contacts (6 mm2 active area). We explored the performance under synchrotron x-rays at the Imaging and Medical Beamline, Australian Synchrotron using two different flexible substrates, Kapton and PET. Using Kapton substrates we obtained an x-ray sensitivity of (1958±31) pC/Gy/cm2 without bias. An energy dependence across energies between (47–87.5) keV was observed and validated with Geant4 simulations to be caused by the high-Z contacts which can be improved by replacing with organic low-Z contacts. The sensor resolved 50µm-wide x-rays averaged across 50 microbeams with a full-width-half-max of (51.6±1.9) µm. By contrast, devices with PET substrates showed significant broadening of the microbeam (58.7±3.6) µm and revised polarity of the signal during x-ray sensitivity measurements. This observation was verified with device simulations to be a result of x-ray induced electrostatic charge in the PET layer. The radiation stability of the organic x-ray sensor was demonstrated to match flexible silicon-based x-ray sensors with a decrease of 35% in x-ray performance after 45 kGy. This work is the first to report the use of a flexible organic x-ray sensor under synchrotron x-rays with high spatial resolution and improved radiation stability but highlights the important role of the surrounding substrate/contact materials when designing wearable x-ray technology.

Presented author:
Maria Karampiperi - Medical Radiation Physics, Dept. of Translational Medicine, Lund University

Authors:
1. - Maria Karampiperi, Medical Radiation Physics, Dept. of Translational Medicine, Lund University, Sweden 2. - Lamprini Malletzidou, Laboratory of Archaeometry and Physicochemical Measurements, Athena - Research and innovation Center in Information, Communication and Knowledge Technologies, Xanthi, Greece 3. - Anna Mrozik, Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Krakow, Poland 4. - Christopher L. Rääf, Medical Radiation Physics, Dept. of Translational Medicine, Lund University, Sweden 5. - Nikolaos Α. Kazakis, Laboratory of Archaeometry and Physicochemical Measurements, Athena - Research and innovation Center in Information, Communication and Knowledge Technologies, Xanthi, Greece 6. - Christian Bernhardsson, Medical Radiation Physics, Dept. of Translational Medicine, Lund University, Sweden

Table salt (NaCl) has been widely investigated for its luminescence properties and its potential use in retrospective dosimetry for radiological or nuclear (R/N) emergencies [1],[2]. It has been suggested as a “citizen-dosemeter”, when measured with optically stimulated luminescence (OSL) [3],[4]. Broader knowledge and understanding are indeed required if using the thermoluminescence (TL) signal for individualized screening. Here, NaCl in the form of either grain samples or compressed into pellets was used. When the samples were irradiated and measured by TL for the first time, three peaks appeared, at approximately 106, 178 and 377°C for grains and at 124, 223 and 425°C for pellets. During a second irradiation and TL measurement, the shape of the TL-curves changed, and new peaks appeared, at 96°C and 246°C for the grains, and at 114°C and 308°C for the pellets, indicating changes in the crystalline structure. Composition analysis and emission spectra of NaCl are expected to shed light on the source of these differences. Annealing is also investigated as a potential procedure to eliminate this discrepancy between the different types of read-outs. Other important TL properties are also studied, such as dose response, sensitization, fading, pellets’ ageing and detection limits. An attempt of a computerized curve deconvolution analysis (CCDA) is also made. References [1] S. Druzhyna et al., Nucl. Phys. B377, 67-76 (2016), doi: 10.1016/j.nimb.2016.04.024 [2] Ü. R. Yüce et al., Rad. Meas. 102, 1-9 (2017), doi: 10.1016/j.radmeas.2017.05.013 [3] L. Waldner et al., Rad. Meas. 119, 52-57 (2018), doi: 10.1016/j.radmeas.2018.09.001 [4] C. Bernhardsson et al., Health Phys. 103(6), 740-749 (2012), doi: 10.1097/HP.0b013e31825d0e1b

Presented author:
Željka Knezevic - Rudjer Boskovic Institute

Authors:
1. Marija Majer, Rudjer Boskovic Institute, Croatia 2. Iva Ambrožová, Nuclear Physics Institute of the CAS, Czech Republic 3 .Miguel Á. Caballero-Pacheco, Universitat Autònoma de Barcelona, Spain and INFN Laboratori Nazionali di Frascati, Italy 4. Marie Davídková, Nuclear Physics Institute of the CAS, Czech Republic 5. Marijke De Saint-Hubert, Belgium Nuclear Research Centre, Belgium 6. Carles Domingo, Universitat Autònoma de Barcelona, Spain 7. Liliana Stolarczyk, Danish Centre for Particle Therapy, Denmark 8. Gloria Vilches-Freixas, Maastro Clinic, Netherlands 9. Pawel Olko, Institute of Nuclear Physics PAN, Poland

Dosimetry of pulsed radiation fields with active devices is demanding because high dose rate pulses lead to local signal saturation and reduced detector response. Since passive solid state detectors are in principle insensitive to dose rate effects, they have proven to be ideally suited for dosimetry of pulsed beams, including out-of-field doses of scattered radiation. The EURADOS 9 (Radiation Dosimetry in Radiotherapy) working group organized a measurement campaign of the secondary radiation doses generated by the pulsed proton beam of the Mevion S250i synchrocyclotron at Maastro Clinic (Maastricht, the Netherlands). The accelerator is mounted directly on the scanning gantry and equipped with a range modulator and an adaptive aperture to provide a laterally sharp-edged scanning proton beam. These beam formation elements, located close to the patient, are an additional source of scattered radiation, including neutrons. Measurements of secondary radiation dose distribution were performed in a water phantom (600 × 300 × 300 mm3) previously used in EURADOS WG9 experiments using different types of passive detectors (1). Neutron and gamma-ray doses were measured with thermoluminescent (MTS-7, MTS-6 and MCP-n, TLD-700), radiophotoluminescent (GD-352M and GD302-M), and polyallyldiglycol carbonate (PADC) -based (C12H18O7) track-etched detectors. Detectors were mounted in PMMA pipes at different distances from the isocenter. 5 frames were positioned at 5 depths along the beam direction with 5 pipes per frame perpendicular to the beam direction. The combination of solid-state detectors used in the present experiment allowed us to determine the dose contributions of gamma rays, thermal neutrons, and fast neutrons. The measured out-of-field doses obtained by the set of passive detectors will be summarized, discussed, and compared with results obtained in similar experiments in cyclotron-based facilities, where beam degradation occurs far from the patient position.

Presented author:
Abel Fernando Martínez Cruz - Universidad de Sonora

Authors:
1,*.- A. F. Martínez-Cruz, Departamento de Investigación en Polímeros y Materiales de la Universidad de Sonora, Hermosillo, Sonora, México 1.-V. R. Orante-Barrón, Departamento de Investigación en Polímeros y Materiales de la Universidad de Sonora, Hermosillo, Sonora, México 1.-C. Cruz-Vazquez, Departamento de Investigación en Polímeros y Materiales de la Universidad de Sonora, Hermosillo, Sonora, México 2.-R. Bernal, Departamento de Investigación en Polímeros y Materiales de la Universidad de Sonora, Hermosillo, Sonora, México

Solution combustion synthesis (SCS) is a technique in which a highly exothermic redox chemical reaction is carried out between a metal nitrate and a fuel, resulting in nanocrystals with composition consistent with the initial reagents [1]. It is reported that introduction of alkaline metal ions into lanthanide-doped MgO enhances the photoluminescence (PL) signal significantly due to compensation charge effects with lanthanide ions [2], [3]. The presence of interstitials defects, such as F and V centers, within the crystal lattice of the host, result in a reduction of photon energy below the band gap energy. The mentioned defects can induce charge imbalances in states which result in the emergence of new electronic states within the band gap. Such energy states are believed to be the primary sources of luminescence in MgO, contributing to its exceptional luminescent properties [4]. According to the antecedents mentioned above, TL properties of annealed MgO chemically modified with Nd and Li using glycine as fuel, obtained by solution combustion (SCS), are presented in this work for the very first time. TL glow curves obtained after exposing to beta radiation MgO chemically modified with Nd and Li powder samples, displayed at least four maxima, hence, the main peak located at ~ 320 °C. MgO chemically modified with Nd and Li powder samples showed remarkable TL dosimetry properties according to the results obtained in this work, dose response without saturation evidence between 10-320 Gy, and a linear trend within the 10-80 Gy dose range, as well as asymptotic behavior of the TL fading for times up to 16 hours. The above characteristics place the material promising for dosimetry applications in the medium and high-dose range. [1] V. R. Orante Barrón, F. M. Escobar Ochoa., C. Cruz Vázquez., R. Bernal S., (2016). Thermoluminescence of novel MgO–CeO2 obtained by a glycine-based solution combustion method. [2] F. Gu, Ch. Li, H. B. Jiang, Journal of Crystal Growth 289 (2006) 400–404. [3] F. Gu, Ch. Li, H. Cao, W. Chao, Y. Hu, J. Chen, A. Chen, Journal of Alloys and Compounds 453 (2008) 361–365. [4] P. Bishnoi, G. Dhiman, R. Brajpuriya, K. Hwa Chae, S.O Won, A. Vij. (2024).

Presented author:
FRANCESCO D'ERRICO - Università di Pisa

Authors:
Francesco d’Errico, Scuola di Ingegneria, Università di Pisa, Pisa, Italy — Andrea Marini, Scuola di Ingegneria, Università di Pisa, Pisa, Italy — Debora Siqueira, Scuola di Ingegneria, Università di Pisa, Pisa, Italy — Susana de Souza Lalic, Departamento de Física, Universidade Federal de Sergipe, São Cristóvão-SE, Brazil — Maurizio Marrale, Dipartimento di Fisica e Chimica, Università degli Studi di Palermo, Palermo, Italy — Andrea Dell’Orso, Ospedale San Giuseppe, Azienda USL Toscana Centro, Empoli, Italy — Guglielmo Manenti, Dipartimento di Biopatologia e Diagnostica per Immagini, Università di Roma 2, Tor Vergata, Italy — Giuseppe Felici, Sordina IORT Technologies SpA, Aprilia, Italy

This research utilizes PVA-GTA Fricke gels for three-dimensional dosimetry of the SIT-Sordina ElectronFlash accelerator, a cutting-edge electron LINAC designed to explore the FLASH radiotherapy effect. PVA-GTA Fricke gels offer a promising alternative to traditional gel dosimeters due to their superior stability, sensitivity, reproducibility, and tissue equivalence. Synthesized via chemical cross-linking of polyvinyl alcohol (PVA) with glutaraldehyde (GTA), these hydrogels exhibit low post-irradiation diffusion of ferric ions and excellent dosimetric performance. Their linear dose-response, verified up to 25 Gy, makes them ideal for high-resolution 3D dosimetry in the unique conditions of FLASH irradiation. The ElectronFlash accelerator provides unparalleled flexibility in beam parameter control, including dose per pulse, average dose rate, and instantaneous dose rate. This allows experiments to range from conventional radiotherapy conditions to extreme FLASH regimes (>1 Gy per pulse, >100 Gy/s). Key features such as dual nominal electron energies (7 and 9 MeV), diverse applicators, and real-time monitoring systems ensure precise delivery and reproducibility of irradiation parameters. This study combines PVA-GTA gels with Electron Flash technology to measure 3D dose distributions. Results are compared to radiochromic films and alanine dosimetry under varied FLASH and conventional radiation conditions. The versatility of the ElectronFlash system enables precise investigation of irradiation parameter dependencies, such as dose per pulse, pulse repetition frequency, and average dose rate, which are critical for understanding the FLASH effect's radiobiological mechanisms. By combining advanced dosimetric materials with cutting-edge beam delivery technology, this study aims to establish robust protocols for FLASH-RT dosimetry, paving the way for its clinical implementation and the optimization of accelerator designs for future therapeutic applications.

Presented author:
Alexia Oliveira Silva - Universidade de São Paulo

Authors:
1. - Alexia O. Silva, Universidade de São Paulo, Brazil 2. -Yasmim F. Amorim, Instituto Federal de São Paulo, Brazil 3. -Matheus C. S. Nunes, Universidade Estadual Paulista, Brazil 4. - Carina Ulsen, Universidade de São Paulo, Brazil 5. -Elisabeth M. Yoshimura, Universidade de São Paulo, Brazil 6. -Neilo M. Trindade, Universidade de São Paulo, Brazil

Luminescence dosimeters are materials used to measure the energy absorbed from ionizing radiation by detecting the emitted signal after being stimulated. The primary techniques in dosimetry include thermoluminescence (TL), which involves a thermal stimulus, and optically stimulated luminescence (OSL), which uses light as stimulus. Given the widespread use of X-ray irradiation in medical applications, this study provides a detailed analysis of the TL and OSL properties of Brazilian alexandrite pellets (BeAl2O4: Cr3+) following exposure to X-rays. Firstly, structural and compositional analysis of alexandrite powder was conducted to assess the quality of the samples. X-ray diffraction (XRD) pattern revealed that the sample consists primarily of chrysoberyl (alexandrite), with traces amounts of quartz, kaolinite and phlogopite. X-ray fluorescence (XRF) and Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) confirmed the presence of chromium (Cr) and iron (Fe). Alexandrite pellets exhibited an intense TL signal when previously irradiated with X-ray, characterized by five glow peaks centered at 75, 130, 175, 250 and 300°C. The activation energy (E) and frequency factor (s) were estimated using first order and general-order kinetic equations. Furthermore, the OSL curve deconvolution revealed three components, characterized as fast, medium, and slow. The results obtained showed that both OSL and TL signals exhibited linear dependence on X-ray exposure. Moreover, the pellets have low fading at room temperature, maintaining 63% of the OSL signal after 10 days of storage. Overall, the results demonstrate that alexandrite is sensitive to X-rays irradiation and holds potential to applications in radiation dosimetry. Acknowledgments: A. O. Silva thanks to FAPESP (#2024/14974-1; #2023/04955-7). Y. F. Amorim thanks to FAPESP (#2022/06690-8). M. C. S. Nunes personally acknowledges funding by FAPESP (#2021/12758-1; #2022/14516-8). C. Ulsen thanks to FINEP (#01.18.0041.00). E. M. Yoshimura is grateful to FAPESP (#2018/05982-0) and CNPq (#311657/2021-4). N. M. Trindade thanks FAPESP (#2018/05982-0; #2019/05915-3; #2024/03006-4) and CNPq (#409338/2021-4;#306929/2022-8).

Presented author:
Christina Stengl - German Cancer Research Center (DKFZ)

Authors:
1. Christina Stengl, German Cancer Research Center (DKFZ) and University of Heidelberg, Germany 2. Jeppe B. Christensen, Paul Scherrer Institute (PSI), Switzerland 3. Iván D. Muñoz, German Cancer Research Center (DKFZ) and National Center for Radiation Research in Oncology (NCRO), Germany 4. Alexander Neuholz, Heidelberg Ion Beam Therapy Center (HIT), Germany 5. Stephan Brons, Heidelberg Ion Beam Therapy Center (HIT), Germany 6. Eduardo G. Yukihara, Paul Scherrer Institute(PSI), Switzerland 7. Jakob Liermann, Heidelberg University Hospital (UKHD) and University of Heidelberg, Germany 8. Oliver Jäkel, German Cancer Research Center (DKFZ) and National Center for Radiation Research in Oncology (NCRO), Germany 9. José Vedelago, Heidelberg University Hospital (UKHD) and German Cancer Research Center (DKFZ), Germany

Pancreatic cancer remains one of the deadliest malignancies, with a five-year survival rate of only 5 % to 10 %. Conventional radiotherapy encounters significant challenges in treating this aggressive disease, primarily due to the inherent radio-resistance of pancreatic tumors and the effects of respiratory motion, which can compromise the accuracy of dose delivery. These factors hinder the development of effective, safe, and precise treatment strategies for pancreatic cancer patients. To address these critical issues, we developed an anthropomorphic abdominal phantom with dynamic organ motion feature, capable of simulating realistic breathing-induced motion. This phantom includes a deformable diaphragm and peritoneum, alongside 3D-printed models of the pancreas, the kidneys, the duodenum, and a segment of the spine. A computer-controlled motor-driven system was employed to simulate respiratory motion with amplitudes of 5 mm, 10 mm, and 20 mm. Various dosimeters, including ionization chambers, radiochromic films, and optically stimulated luminescence detectors (OSLDs), were used to simultaneously measure dose distributions within the pancreatic tumor and surrounding organs at risk (OARs). Carbon-ion irradiation, designed to mimic a typical patient treatment plan, was delivered with and without gating as motion management tool. Our results demonstrate that respiratory motion of 20 mm introduces significant underdosage of over 30 %, which undermines the efficacy of carbon-ion radiotherapy. The impact on OARs varied based on their position relative to the moving tumor. Gating reduced dose inhomogeneity within the target and increased the dose by up to 20 % compared to motion alone, without affecting the dose to the organs at risk. The organ-motion phantom serves as a high-fidelity model for testing and refining adaptive radiotherapy approaches, bridging the gap between pre-clinical studies and patient treatments. This research marks a crucial step toward overcoming the challenges of breathing induced organ motion during pancreatic cancer radiotherapy.

Presented author:
Yaroslav Zhydachevskyy - Institute of Physics, Polish Academy of Sciences

Authors:
1. - Yaroslav Zhydachevskyy 2. - Magda Baran 3.- Vasyl Stasiv 4. - Oleksandr Poshyvak 5. - Sergii Ubizskii 6. - Andrzej Suchocki

The work is devoted to development of new storage phosphor material based on Bi3+ activated (Y,Lu)AlO3 perovskite with Zeff ≥ 31.4 applicable for radiation monitoring. The idea of ionizing irradiation source recognition utilizing measurements of absorbed dose using at least two different TSL/OSL detectors with strongly different effective atomic numbers has been around for a long time. However, to date, this approach has not been implemented in practice mainly due to the lack of appropriate detectors made of high-Z materials. Besides, the high-Z storage phosphors having high brightness, efficient OSL and short luminescence lifetime are of particular interest for X-ray imaging. Our previous efforts were focused on development and investigation of YAlO3:Mn2+ TSL/OSL detectors and their implementation in the tandem dosimeter allowing recognition of unknown radiation source. YAlO3:Mn2+ detectors were proven to be quite efficient and suitable for this purpose, but have some drawbacks, such as long afterglow, emission in the visible range that requires a special and complex OSL reading system. This is particularly inconvenient when it should be used alongside with the UV-emitting OSL phosphors like BeO or Al2O3:C. Therefore we decided to develop UV-emitting storage phosphor based on YAlO3 perovskite. Bi3+-activated (Y,Lu)AlO3 microcrystalline powders were successfully synthesized by sol-gel technique. The powders as well as ceramic samples produced from these powders were studied. In particular, TSL, OSL and some dosimetric properties of the new material have been studied. CW-OSL mode has been used with the visible blue (450 nm) stimulation and UV (320 nm) registration. As the spectroscopic properties of the new material are comparable with BeO, our measurements were performed in comparison with Thermalox ceramics. The results obtained indicate a high application potential of the new material for radiation monitoring, especially for the tasks were the high atomic number of the material can be exploited.

Presented author:
Olga Avila - Instituto Nacional de Investigaciones Nucleares

Authors:
1. Olga Ávila, Instituto Nacional de Investigaciones Nucleares, Mexico 2. Evangelina Figueroa-Medina, Corporación Oncológica México Americana, Aguascalientes, Mexico 3. Norma Paola Martínez-García, Instituo Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico 4. José María Chávez-Castillo, Facultad de Ciencias, UNAM, Mexico 5. Isabel Gamboa-deBuen, Instituto de Ciencias Nucleares, UNAM, Mexico

Research area of interest: Dosimetry for Medicine and Biology Introduction: Electron beam therapy is used in the treatment of superficial tumors like cancer of skin regions, or total skin (e.g. mycosis fungoides) among other applications. Irradiations are performed with linear accelerators (LINAC). A precise dosimetry may be attained using thermoluminescent (TL) dosimeters. This work reports results of TL response of TLD-100, TLD-100H and TLD-900 dosimeters exposed to 6-22 MeV electron beams. Methods: Dosimeters were exposed to electrons from a LINAC at “Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán” (INCMNSZ) with energies between 6 and 22 MeV at doses between 0.05 and 3 Gy. Readouts were performed 48-72 h after irradiations with the aid of a 3500 Harshaw TL Reader at “Instituto de Ciencias Nucleares, UNAM” (ICNUNAM). Dosimeters were also exposed to gamma radiation from 60Co at the Ionizing Radiation Secondary Laboratory, Instituto Nacional de Investigaciones Nucleares (ININ). Monte Carlo simulations of energy deposition using Penelope code were also performed. Results: Glow curves, dose response curves and relative TL electron/gamma response were obtained. Conclusions: Values of relative TL electron to gamma response (RR) for the studied dosimeters were found to be lower than one for TLD-100 and TLD-900 and greater than one for TLD-100H. Differences between 3 and 10% with Monte Carlo RR were found for TLD-100 and TLD-100H while greater differences between 4 and 19% were found for TLD-900. This result for TLD-900 is attributed to the lower quality control in its manufacture. Acknowledgements: Authors acknowledge support from ININ-FI-002.

Presented author:
José Vedelago - Heidelberg University Hospital (UKHD)

Authors:
1.- Long-Yang Jan Thai, German Cancer Research Center (DKFZ) and Heidelberg University, Germany 2.- Stefan Schmidt, Heidelberg University Hospital (UKHD) and German Cancer Research Center (DKFZ), Germany 3.- Alexandra Walter, German Cancer Research Center (DKFZ) and Karlsruhe Institute of Technology (KIT), Germany 4.- Kristina Giske, German Cancer Research Center (DKFZ) and National Center for Radiation Research in Oncology (NCRO), Germany 5.- José Vedelago, Heidelberg University Hospital (UKHD) and German Cancer Research Center (DKFZ), Germany

Ion beam radiotherapy is an advanced cancer treatment modality known for its optimal tissue-sparing capabilities. As a result of the ion interactions, a small fraction of secondary neutrons with several hundred MeV is generated. These neutrons reach healthy tissue far away from the treatment volume, increasing the late-effects probability. Accurate secondary neutron dose measurement is essential for improving late-effect probability estimations. Fluorescent Nuclear Track Detectors (FNTDs) are ideal candidates since they are versatile passive solid-state detectors allowing visualization of charged particle tracks induced by neutrons. In addition to the FNTD’s high spatial resolution, their small size opens the possibility for in-phantom measurements. Present image processing tools mainly utilize classical approaches like filtering, intensity thresholding and principal component analysis to evaluate FNTD images. These procedures result in the discrimination between recoil protons and delta-electrons, caused by neutrons and gamma rays, respectively. Determining the recoil proton track density can estimate the dose due to a proportional relationship. The accuracy of the track analysis can be optimized by exploiting the potential of machine learning. Our approach is to train a machine learning model for track segmentation and expand the informational output from type and number of particles to quantities like linear energy transfer (LET) and energy fluence. The segmentation is done with a nnU-Net model, trained with FNTD images from experimental measurements with a broad-spectrum 241Am-Be source and with mono-energetic neutron fields within 1.2 MeV to 19 MeV. The training data is labelled by the classical PCA approach. This model will be paired with reference images generated by Monte Carlo (MC) simulations with FLUKA at the same energies, validating the simulation. Later, the MC will be used to generate training data for the machine learning model, aiming at covering the energy range of secondary neutrons in ion beam radiotherapy.

Presented author:
Alvaro de Farias Soares - University of Palermo

Authors:
1. Alvaro de Farias Soares - Department of Physics and Chemistry “Emilio Segrè”, University of Palermo, Italy. 2. Mattia Romeo - Department of Physics and Chemistry “Emilio Segrè”, University of Palermo, Italy. 3. Grazia Cottone - Department of Physics and Chemistry “Emilio Segrè”, University of Palermo, Italy. 4. Maria Cristina D’Oca - Department of Physics and Chemistry “Emilio Segrè”, University of Palermo, Italy. 5. Giuliana Milluzzo - Istituto Nazionale di Fisica Nucleare (INFN), Italy. 6. Francesco Romano - Istituto Nazionale di Fisica Nucleare (INFN), Italy. 7. Fabio Di Martino - Centro Pisano Ricerca e Implementazione Clinica Flash Radiotherapy (CPFR@CISUP), Italy. 8. Francesco d’Errico - School of Engineering, University of Pisa, Italy. 9. Maurizio Marrale - Department of Physics and Chemistry “Emilio Segrè”, University of Palermo, Italy.

The widespread use of radiation requires accurate measurement either in real-time or post-irradiation, especially with the recent high-dose rates fields and minibeams. In this regard, there is an increasing interest towards Fricke gels (FG), given their characteristics of tissue-equivalence and 3D shape. FG is based on the oxidising process of ferrous ions (Fe2+) into ferric ones (Fe3+) as a result of irradiation exposure. This change is measured via magnetic resonance imaging (MRI) or optical absorption spectroscopy. However, over time, diffusion of ions in the matrix occurs and produces blurring effects in dose distributions, hence, both over and underestimation of doses. This hampers its use as usually the reading of the gel cannot be done soon after the procedure. Experimental approaches dealing with this problem rely on either the incorporation of chelating agents to reduce ions' mobility or matrix modifications. This work adopts deep learning along with Physics Informed Neural Networks (PINNs) to solve partial differential equations related to inverse problems. Exploiting Physics laws, models are trained to predict a pre-diffusion condition. Models´ inputs include Fe3+ distribution at a given time t, boundary conditions and the diffusion coefficient, D. The value of D originates from experimental data. Predictions are performed in 1D, 2D and 3D distributions up to 100 hours after irradiation. The modelling is compared to optical absorbance data from irradiated poly-vinyl-alcohol with glutaraldehyde as a linking agent (PTA-GTA). Results are given in terms of mean square errors and gamma analysis, and show good agreement quantified by the gamma index, indicating that this approach has the potential to overcome this issue. This work was partially funded by the European Union - Next Generation EU with the Projects SAMOTHRACEs (MUR, PNRR-M4C2, ECS_00000022) and DALI’ (PNRR MUR M4 C2 Inv. 1.5 CUP B83C22003930001).

Presented author:
Yuho Hirata - Japan Atomic Energy Agency

Authors:
1. Yuho Hirata, Japan Atomic Energy Agency, Japan 2. Takeshi Kai, Japan Atomic Energy Agency, Japan 3. Tatsuhiko Ogawa, Japan Atomic Energy Agency, Japan 4. Yusuke Matsuya, Hokkaido University, Japan 5. Tatsuhiko Sato, Japan Atomic Energy Agency, Japan 6. Kenichi Watanabe,Kyushu University, Japan 7. Takumi Kato, Nara Institute of Science and Technology, Japan 8. Noriaki Kawaguchi, Nara Institute of Science and Technology, Japan 9. Takayuki Yanagida, Nara Institute of Science and Technology, Japan

CaF2:Ce has a high potential to be used as a dosimeter due to its high optically stimulated luminescence (OSL) intensity. However, when the CaF2:Ce is irradiated with swift ions, the OSL intensity per absorbed dose decreases in the Bragg peak region due to quenching effects. Accurately measuring dose for various types of radiation with a phosphor detector requires understanding the mechanism of the quenching effect based on electron behavior at the atomic scale. Traditionally, quenching effects in phosphors have been analyzed through energy deposition density, using linear energy transfer (LET) as a metric. However, the relationship between quenching effects and LET varies with ion species; therefore, LET alone cannot explain the phenomenon. To address this, we employed Monte Carlo simulations to explicitly evaluate the generation of excited electrons and consider the process leading to luminescence. The track-structure simulation in general-purpose Particle and Heavy Ion Transport code System (PHITS) enables tracking of individual atomic interactions, allowing us to simulate the process of excited electron generation within phosphors. In this study, we modeled the quenching effect in CaF2:Ce irradiated with helium and carbon ions based on a hypothesis that quenching results from the local saturation of trap centers. We then compared the simulation results of dose distribution with the corresponding experimental data using CaF2:Ce. The comparison suggests that the quantum yield of OSL is a critical parameter influencing the quenching effect in CaF2:Ce. These findings are expected to contribute to the development of improved phosphor detectors.

Presented author:
Sita Gandes Pinasti - Belgian Nuclear Research Centre / SCK CEN

Authors:
1. Sita Gandes PINASTI, Belgian Nuclear Research Centre, Belgium 1. Sita Gandes PINASTI, Université Libre de Bruxelles, Belgium 2. Liviu-Cristian MIHAILESCU, Belgian Nuclear Research Centre, Belgium 3. Mahmoud ABDELRAHMAN, Belgian Nuclear Research Centre, Belgium 4. Olivier VAN HOEY, Belgian Nuclear Research Centre, Belgium 5. Anna PÁNTYA, HUN-REN Centre for Energy Research, Hungary 6. Dorottya JAKAB, HUN-REN Centre for Energy Research, Hungary 7. Csilla RUDAS, HUN-REN Centre for Energy Research, Hungary 8. Márton ZAGYVAI, HUN-REN Centre for Energy Research, Hungary 9. Tamás PÁZMÁNDI, HUN-REN Centre for Energy Research, Hungary 10. Filip VANHAVERE, Belgian Nuclear Research Centre, Belgium 11. Nicolas PAULY, Université Libre de Bruxelles, Belgium

Radiation worker dose assessment by personal dosimeters is limited by practical challenges, such as workers occasionally forgetting to use their dosimeters or wearing them incorrectly, furthermore the single-point measurements may not be representative for the whole body. These issues are particularly pronounced in neutron workplaces, where dosimeters can significantly over- or underestimate the dose. Computational neutron dosimetry presents an alternative monitoring method. This study aims to investigate the feasibility of using computational neutron dosimetry in a real neutron workplace, namely at the Budapest Research Reactor. The Raylab DIAMON neutron spectrometer and the Berthold LB6411 ambient neutron monitor were used for rapid neutron field characterization. By combining the measured dose rate map with a camera-based motion tracking system, it was possible to rapidly calculate the neutron dose accumulated by a worker. Computational dosimetry estimated a dose rate of 0.26 µSv/min in H*(10), closely matching the 0.2 µSv/min recorded by physical dosimetry in Hp(10). This study demonstrated that worker movement can be accurately tracked, provided there are no obstacles between the camera and the worker. Additionally, dose rate mapping can be done quickly and computational neutron dosimetry can effectively estimate worker dose in real neutron workplace fields, as long as the radiation field remains stable. This approach has the potential to complement physical dosimeters, providing improved accuracy in complex neutron fields. Combining directional and spectral data could also enable mapping in terms of Hp(10) or effective dose, this however requires further investigation.

	ABC auditorium - Facultad de Ciencias, UNAM	Carlos Graef auditorium - Facultad de Ciencias, UNAM
08:30 - 09:00	Registration	Registration
09:00 - 09:30	Invited Talk 3 Marcelino Barboza Flores - UNISON "50 years of thermoluminescence research in México"
09:30 - 10:30	Materials I Moderators: Maria Karampiperi & José Fernando Diniz Chubaci
09:30 - 09:45	Peter Balling - Aarhus University "A novel, tissue equivalent material for three-dimensional dosimetry based on optically stimulated luminescence"
09:45 - 10:00	Go Okada - Kanazawa Institute of Technology "Development of New RPL Materials for Real-Time Dose Measurements"
10:00 - 10:15	Ilia Filipev - University of Wollongong "Flexible Organic X-ray Sensors under Synchrotron X-rays"
10:15 - 10:30	Muhammad Bakhsh - Qassim University "Synthesis, Characterization and Evaluation of Zinc Dopped and Lithium Co-dopped MgB4O7 Glass as a Thermoluminescence Dosimeter"
10:30 - 12:00	Poster session and coffee break at the Amoxcalli Lobby - Facultad de Ciencias, UNAM	Poster session and coffee break at the Amoxcalli Lobby - Facultad de Ciencias, UNAM
12:00 - 13:30	Materials II Moderators: Peter Balling & Nancy Zuñiga	Dosimetry for Medicine & Biology I Moderators: Ivan D. Muñoz & Marija Majer
12:00 - 12:15	Maria Karampiperi - Medical Radiation Physics, Dept. of Translational Medicine, Lund University "Characterization of thermoluminescence properties of salt grains and NaCl pellets for R/N emergencies"	Željka Knezevic - Rudjer Boskovic Institute "Solid state dosimetry of secondary radiation produced by HYPERSCAN pulsed pencil scanning proton beam"
12:15 - 12:30	Abel Fernando Martínez Cruz - Universidad de Sonora "Thermoluminescence of MgO Chemically Modified with Nd and Li Ions, Obtained by Glycine-based Solution Combustion Synthesis"	FRANCESCO D'ERRICO - Università di Pisa "Three-Dimensional Dosimetry of FLASH Electron Beams Using PVA-GTA Fricke Gels"
12:30 - 12:45	Alexia Oliveira Silva - Universidade de São Paulo "THERMOLUMINESCENCE AND OPTICALLY STIMULATED LUMINESCENCE OF X-RAY-IRRADIATED NATURAL ALEXANDRITE"	Christina Stengl - German Cancer Research Center (DKFZ) "Assessing Respiratory Motion Effects and Gating Benefits in Carbon Ion Therapy for Pancreatic Cancer: In-Phantom Dose Analysis"
12:45 - 13:00	José Fernando Diniz Chubaci - Universidade de São Paulo "Silver-Doped Calcium Silicate Glass for Radio-Photoluminescent Dosimetry"	Roberto Bedogni - Istituto Nazionale di Fisica Nucleare - Laboratori Nazionali di Frascati (INFN-LNF) "Rad-hard silicon carbide thermal neutron detectors for quality assurance in BNCT"
13:00 - 13:15	Yaroslav Zhydachevskyy - Institute of Physics, Polish Academy of Sciences "New UV-emitting high-Z storage phosphor material for TSL/OSL dosimetry"	Olga Avila - Instituto Nacional de Investigaciones Nucleares "Thermoluminescent response under electron irradiation"
13:15 - 13:30	Chahra-Zed Benkhelifa - Algiers Nuclear Research Center/CRNA "A comparative study of the dosimetric features of commercial α-Al2O3:C and α-Al2O3:Sb."	Fernanda C Rodrigues-Machado - McGill University "A cavity-enhanced hydrated electron sensor for real-time, tissue-equivalent radiation dosimetry"
13:30 - 15:00	Lunch at the Physics Institute garden	Lunch at the Physics Institute garden
15:00 - 15:30	Invited Talk 4 Tatsuhiko Sato - Japan Atomic Energy Agency "General Features of PHITS and its Applications to Response Calculations of Solid-State Detectors"	Invited Talk 4 (via Zoom) Tatsuhiko Sato - Japan Atomic Energy Agency "General Features of PHITS and its Applications to Response Calculations of Solid-State Detectors"
15:30 - 16:45	Computational detection modelling and dosimetry Moderators: Olga Ávila & Massimo Piccinini	Sponsor Session Moderators: Joe Rotunda & Susana de Souza Lalic
15:30 - 15:45	José Vedelago - Heidelberg University Hospital (UKHD) "A Machine Learning tool for neutron dosimetry with Fluorescent Nuclear Track Detectors"	Chiyoda Technol Corporation Miki Hirata - International Affairs Department, Chiyoda Technol Corporation "Overview of radiation dosimeters based on radio-photoluminescence (RPL) and poly allyl diglycol carbonate (PADC)"
15:45 - 16:00	Alvaro de Farias Soares - University of Palermo "Tackling the problem of diffusion in Fricke gels dosimeters through a deep learning algorithm"	Chiyoda Technol Corporation Miki Hirata - International Affairs Department, Chiyoda Technol Corporation "Overview of radiation dosimeters based on radio-photoluminescence (RPL) and poly allyl diglycol carbonate (PADC)"
16:00 - 16:15	Yuho Hirata - Japan Atomic Energy Agency "Analysis of quenching effects in CaF₂:Ce using PHITS track-structure simulations"	LANDAUER/ALSA Marc MILLION - Landauer-Europe "The latest Landauer’s research & developments on dosimetry systems based on Al2O3:C"
16:15 - 16:30	Sita Gandes Pinasti - Belgian Nuclear Research Centre / SCK CEN "Computational personal neutron dosimetry at the Budapest Research Reactor"
16:30 - 16:45	Wilmer Melo Bernal - Secretaria de Educación Distrital, Bogotá "Monte Carlo and analytical simulation of the angular-energy distribution of recoil protons in fluorescent nuclear track detectors with an external converter"
16:45 - 18:30	Coffee break	Coffee break

Presented author:
Jorge Altair Duarte-Rodríguez - Universidad de Sonora

Authors:
Jorge Altair Duarte-Rodríguez, Programa de Posgrado en Ciencias, Departamento de Investigación en Física, Universidad de Sonora, Hermosillo, Sonora, 83000 México María Inés Gil-Tolano, Departamento de Investigación en Física de la Universidad de Sonora, Hermosillo, Sonora, 83000, México Epifanio Cruz-Zaragoza, Instituto de Ciencias Nucleares, UNAM, A.P. 70-543, Ciudad de México, 04510, México Rodrigo Meléndrez-Amavizca, Departamento de Investigación en Física de la Universidad de Sonora, Hermosillo, Sonora, 83000, México Marcelino Flores-Barboza, Departamento de Investigación en Física de la Universidad de Sonora, Hermosillo, Sonora, 83000, México

The coloration of Himalayan salt ranges from white to pink, red, and black, primarily due to the presence of impurities such as iron, potassium, magnesium, and calcium. The varying proportions of these impurities affect the optical and thermal properties of the salt. In this study, we conducted a comparative analysis of the pigmentation of Himalayan salt using thermoluminescence (TL), which was exposed to beta radiation from 90Sr/90Y. We categorized the salt grains based on their pigmentation into four groups: white, pink, red, and black. The TL analysis revealed two broad bands with maxima around 130°C and 240°C for most samples, while the black pigmented sample showed lower TL intensity and several overlapping TL peaks with maxima at approximately 110°C, 145°C, and 296°C. The TL dosimetry for the white, pink, and red samples displayed a linear response within the range of 0.083 to 10 Gy. In contrast, the black pigmented salt exhibited a linear range from 0.083 to 300 Gy, with no evidence of saturation. Repeatability studies indicated maximum errors of 2%, 2.5%, 1.7%, and 1.7% for the salt samples, ranked from least to most pigmented. After 18 days of storage in dark conditions at room temperature, the TL fading percentages were 65%, 56%, 65%, and 35% for the white, pink, red, and black pigmented samples, respectively. Furthermore, energy-dispersive X-ray spectroscopy (EDS) studies identified that the primary impurities present in sodium chloride (NaCl) were oxygen, magnesium, potassium, calcium, sulfur, silicon, aluminum, and iron. Himalayan salt with white pigmentation demonstrated greater sensitivity to radiation in TL, whereas the black pigmented salt exhibited a broader dose range (0.083–300 Gy). Therefore, Himalayan salt is deemed suitable for use as a TL dosimeter.

Presented author:
Alexia Oliveira Silva - Universidade de São Paulo

Authors:
1. - Alexia O. Silva, Universidade de São Paulo, Brazil 2. - Neilo M. Trindade, Universidade de São Paulo, Brazil 3. - E. M. Yoshimura, Universidade de São Paulo, Brazil 4.- C. Ulsen, Universidade de São Paulo, Brazil

Space agencies are focused on understanding the conditions of Martian and lunar surfaces, including radiation levels, to advance technologies for future space missions. One effective approach to assess these environments is by using luminescence to measure the radiation doses absorbed by surface materials, such as sediments and natural minerals. This technique provides valuable insights into the exposure history and stability of these extraterrestrial surfaces. Olivine (Mg,Fe)2SiO4 is a mineral group, whose presence has already been reported in Martian and lunar soils, in addition to making up around 1.5% of the volume of the Earth's crust. Therefore, this work proposes to investigate the effects of ionizing radiation on natural olivine, using the thermoluminescence (TL) technique. TL refers to the luminescence emitted by the recombination of charges thermally released from specific traps within a material, previously irradiated by ionizing radiation. Also, mineralogical and microstructural characterization techniques, such as scanning electron microscopy with energy dispersive spectroscopy (SEM/EDS), X-ray diffraction (XRD) and X-ray fluorescence (XRF), were performed. The TL experiment was conducted in Risø TL/OSL reader by irradiating the sample with a beta source (Sr90/Y90). For TL, the sample was heated to 500°C (1°C/s). From thermoluminescent previous results, it was possible to identify 3 glow curves at ~80°C, 190°C and 340°C. The dose-response experiment suggest that olivine sample has linear behavior up to 10 Gy, after that, it behaves sublinearly. Dosimetric properties as fading, repeatability and reproducibility will be tested. These results will contribute to understanding the viability of olivine as radiation detectors in extraterrestrial environments, such as Mars and the Moon. Acknowledgements: A. O. Silva thanks to FAPESP (#2024/14974-1; 2024/03006-4). N. M. Trindade thanks to FAPESP (#2018/05982-0; #2019/05915-3; 2024/03006-4) and CNPq (#409338/2021-4; #306929/2022-8).

Presented author:
Divanizia Souza - Universidade Federal de Sergipe, UFS

Authors:
1. Anderson M. B. Silva,Instituto de Pesquisas Energéticas e Nucleares/Comissão Nacional de Energia Nuclear IPEN/CNEN, São Paulo, SP, Brazil 2. Marcelo F. Santos, Departamento de Física, Universidade Federal de Sergipe UFS, São Cristóvão, SE, Brazil 3. Danilo O. Junot, Instituto de Física Armando Dias Tavares, Universidade do Estado do Rio de Janeiro UERJ, Rio de Janeiro, RJ, Brazil 4. Patrícia L. Antonio,Instituto de Pesquisas Energéticas e Nucleares/Comissão Nacional de Energia Nuclear IPEN/CNEN, São Paulo, SP, Brazil 5. Linda V. E. Caldas ,Instituto de Pesquisas Energéticas e Nucleares/Comissão Nacional de Energia Nuclear IPEN/CNEN, São Paulo, SP, Brazil 6. Divanizia N. Souza, Departamento de Física, Universidade Federal de Sergipe UFS, São Cristóvão, SE, Brazil

This investigation focuses on CaSO₄ crystals doped with thulium (Tm) and manganese (Mn), synthesized under slow evaporation conditions, with a focus on their applications in thermoluminescent (TL) and optically stimulated luminescent (OSL) dosimetry. Tm was introduced in both its metallic form (Thulium Powder, Tm) and oxide form (Thulium Oxide, Tm₂O₃), with Mn sourced from manganese nitrate (Mn(NO₃)₂·4H₂O) at a 0.1 mol% concentration. Structural characterization through X-ray diffraction confirmed the viability of the employed method, while energy-dispersive spectroscopy (EDS) validated the incorporation of Tm³⁺ and Mn²⁺ ions into the crystal matrices. For dosimetric evaluation, samples were irradiated with beta radiation and formed into Teflon-blended pellets to enhance material strength. Similar emission curves were observed in both the visible and UV regions using Schott BG-39 filter (transmittance in the visible region between 320 nm and 480 nm) and Hoya U-340 filter (transmittance in the UV region between 260 nm and 400 nm). The TL analysis revealed two distinct peaks at 155 °C and 270 °C. Continuous wave (CW) OSL curves with a 40 s integration time displayed a slow-decaying OSL signal that persists over time. This suggests that the traps responsible for the luminescent centers that give rise to the TL signal in these samples are not easily stimulated by the blue LED stimulus. Overall, the CaSO₄:Tm,Mn samples exhibited an intense TL/OSL signal, surpassing some commercially available dosimeters, indicating their potential as a new material with high sensitivity for dosimetric applications.

Presented author:
Ilya Weinstein - Ural Federal University

Authors:
1. - Savchenko S.S., NANOTECH Centre, Ural Federal University, Ekaterinburg, Russia; 2. - Vokhmintsev A.S., NANOTECH Centre, Ural Federal University, Ekaterinburg, Russia; 3. - Weinstein I.A., NANOTECH Centre, Ural Federal University, Ekaterinburg, Russia, Institute of Metallurgy of the Ural Branch of the Russian Academy of Sciences, Ekaterinburg, Russia

Semiconductor quantum dots (QD) core/shell InP/ZnS demonstrate unique properties for the development of sensitive functional media for various elements of nanooptics and photonics, sensors of luminescent nanothermometry, etc. QDs characteristics vary greatly for different synthesis methods, which makes it relevant to study the corresponding energy levels associated with possible structural defects in the quasi-zero-dimensional objects. One of the methods for analysis of the fundamental parameters of these local states is thermally stimulated luminescence (TSL). In this work, we studied the TSL response in the temperature range of 6.5-296 K for ensembles of quantum dots with an average particle size of 2.1 (QD-1) and 2.3 (QD-2). The nanocrystals were characterized by a three-layer structure: InP core, ZnS shell, and modified polyacrylic acid coating. The samples temperature was controlled using a Janis CCS-100/204N helium cryostat. To fill the traps, QDs were irradiated through a UFS-1 filter with an LD (D) deuterium lamp at 6.5 K, and then were linearly heated at a rate of 10 K/min. The luminescent signal was recorded using an Andor based system. The detector was exposed every 30 s, which corresponded to a change in temperature of nanocrystals by 0.5 K. It was shown for the first time that defect states in InP cores of studied ensembles exhibit a TSL response in the form of a single temperature (140 K) and spectral (1.96 and 1.80 eV for QD-1 and QD-2, respectively) maximum. The kinetic parameters for the observed TSL processes were estimated using the initial growth method, peak shape analysis, within the framework of master-equations based on Lambert W-function, and with use of the general order formal kinetics, taking into account the distribution of activation energy for responsible trapping centers.

Presented author:
Teodoro Rivera Montalvo - IPN

Authors:
Teodoro Rivera, IPN, Mexico Alejandra Inzunza, IPN, Mexico Silvia Vicencio, IPN, Mexico Yoshio Villafañe, IPN, Mexico Cesar Díaz, HJM, Mexico Christian Juárez, IPN, Mexico Abraham Vázquez, HCM, Mexico Virgilio Correcher, CIEMAT, España

Dosimetric characteristics of luminescent Detectors for Retrospective TL Dosimetry Teodoro Rivera-Montalvo1, Alejandra Inzunza Lugo1, Silvia J. Vicencio Hernandez1, Yoshio O. Villafañe Bautista1, Cesar A. Díaz Pérez2, Christian J. Juárez Salas1, Abraham Vázquez Valdés3, Virgilio Correcher Delgado4 1Instituto Politécnico Nacional. Av. Legaria 694. 11500, Ciudad de México, México. 2Hospital Juárez de México. Av. Instituto Politécnico Nacional 5160. 07760 ciudad de México, México. 3Hospital Central Militar. Av. Manuel Avila Camacho s/n. 11600 Ciudad de México, México 4CIEMAT-España. Av. Complutense 40. 28040 Madrid, España. *Email: riveramt@hotmail.com Abstract In the present work, thermally stimulated luminescence from crystal luminescent detectors (CLD) under gamma and high energy electron beam (HEEB) source were reported. TL glow curve and other dosimetric properties of lithium tetraborate (Li2B4O7) and hydroxyapatite (HA) were analyzed. Thermoluminescence glow curves of both HA powders and Li2B4O7 were obtained by irradiation with Co-60 gamma radiation sources and high-energy electron beam source. The TL curve of HAS under the effect of gamma irradiation exhibited a TL glow curve with two well-defined peaks. The first one is located around 150°C and the second one is located at 240°C respectively. When irradiated with a high-energy electron beam, a peak centered at around 250°C was observed. Meanwhile Li2B4O7 powders under gamma and HEEB irradiation showed three prominent peaks centered at 170°C, 210°C and 320°C.TL response of CLD as a function radiation dose was increased as radiation dose increased. Experimental results of CLDs under ionizing radiation effect shows a TL glow curve with three glow peaks. These experimental results indicate that studied CLDs can be considered as good candidates as a reference radiation dosimeter in in retrospective dosimetry

Presented author:
Danilo O. Junot - UERJ

Authors:
1 - Danilo O. Junot, Instituto de Física Armando Dias Tavares, Universidade do Estado do Rio de Janeiro UERJ, Rio de Janeiro, RJ, Brazil 2 - Anderson M. B. Silva, Instituto de Pesquisas Energéticas e Nucleares/Comissão Nacional de Energia Nuclear IPEN/CNEN, São Paulo, SP, Brazil 3 - Yara R. R. S. Rezende, Departamento de Física, Universidade Federal de Sergipe UFS, São Cristóvão, SE, Brazil 4 - Divanizia N. Souza, Departamento de Física, Universidade Federal de Sergipe UFS, São Cristóvão, SE, Brazil 5 - Marcos V. S. Rezende, Departamento de Física, Universidade Federal de Sergipe UFS, São Cristóvão, SE, Brazil 6 - Linda V. E. Caldas, Instituto de Pesquisas Energéticas e Nucleares/Comissão Nacional de Energia Nuclear IPEN/CNEN, São Paulo, SP, Brazil

This study explored the potential of utilizing crab shell biowaste as a novel material for thermoluminescent (TL) and optically stimulated luminescent (OSL) radiation detectors. Crab shells (Ucides cordatus), a readily available biowaste material from Atalaia beach in Aracaju, Brazil, were collected and subjected to calcination at 800°C for 2 hours. The resulting powder was then mixed with Teflon in a 2:1 mass ratio and molded into pellets with a diameter of 6 mm and a thickness of 1 mm. These pellets were subsequently sintered at 400°C for 1 hour to enhance their structural integrity. The luminescent properties and dosimetric characteristics of the fabricated crab shell composites were thoroughly investigated using a Risø TL/OSL reader (model DA-20). TL measurements revealed a dominant peak at 155°C and a less intense peak at 350°C. Despite its relatively low temperature, the 155°C peak demonstrated promising dosimetric properties due to its high intensity and acceptable fading characteristics, with only a 12% signal loss observed after 7 days. A strong, rapidly decaying OSL signal was observed, indicating efficient optical stimulation. Emission spectra showed a broad band from 300 to 400 nm. The composites exhibited good homogeneity and reproducibility, linear dose response from 80 mGy to 1 Gy, and milligray-level sensitivity. These findings suggest crab shell composites hold promise as TL/OSL detectors for applications involving beta particles, X-rays, and gamma rays, offering a sustainable and cost-effective solution for radiation dosimetry.

Presented author:
Danilo O. Junot - UERJ

Authors:
1 - Leonardo F. Goes, Instituto de Física Armando Dias Tavares, Universidade do Estado do Rio de Janeiro UERJ, Rio de Janeiro, RJ, Brazil 2 - Anderson M. B. Silva, Instituto de Pesquisas Energéticas e Nucleares/Comissão Nacional de Energia Nuclear IPEN/CNEN, São Paulo, SP, Brazil 3 - Divanizia N. Souza, Departamento de Física, Universidade Federal de Sergipe UFS, São Cristóvão, SE, Brazil 4 - Linda V. E. Caldas, Instituto de Pesquisas Energéticas e Nucleares/Comissão Nacional de Energia Nuclear IPEN/CNEN, São Paulo, SP, Brazil 5 - Danilo O. Junot, Instituto de Física Armando Dias Tavares, Universidade do Estado do Rio de Janeiro UERJ, Rio de Janeiro, RJ, Brazil

Developing new materials for radiation detection is crucial to advance dosimetry research and enable the creation of sensitive and affordable detectors. Thus, this work investigates the development of CaSO4:Tm,Li composites for radiation dosimetry using thermoluminescence (TL) and optically stimulated luminescence (OSL) techniques.. The CaSO4 crystals were synthesized via the slow evaporation method and characterized using X-ray diffraction (XRD), radioluminescence, TL and OSL techniques. XRD analysis confirmed the formation of a single-phase orthorhombic structure. TL measurements revealed characteristic glow curves with peaks around 165 ºC and 275 ºC. All samples were irradiated with a 90Sr/90Y source from the TL/OSL Risø reader. The composites exhibited intense OSL signals, particularly at higher Li concentrations, indicating high sensitivity and potential for use in dosimetry applications. The OSL signal showed slow decay, suggesting good signal stability. The TL emission spectra of the samples showed typical emissions of Tm3+ (455 nm). As no emission corresponding to lithium was identified in the emission spectra, it can be assumed that lithium acts as a capture center and transfers its energy to the nearby Tm3+. All the samples produced showed linearity in the dose range used, and good reproducibility, with variations below 10%. The evaluated dosimetric characteristics denote that all developed composites have potential application as TL/OSL dosimeters.

Presented author:
William Jaramillo Garzón - Universidad Nacional de Colombia

Authors:
1. Adriana Suárez Rojas, Maestría en Ciencias de la Tierra, Universidad Pedagógica y Tecnológica de Colombia, Colombia 2. Fernando Elí Romero Ordoñez, Departamento de Geociencias, Universidad Nacional de Colombia, Colombia 3. Viviane Khoury Asfora, Departamento de Energia Nuclear, Universidade Federal de Pernamabuco, Brazil 4. Helen Jamil Khoury, Departamento de Energia Nuclear, Universidade Federal de Pernamabuco, Brazil 5. William Jaramillo Garzón, Grupo de Física Médica, Universidad Nacional de Colombia, Colombia

Natural fluorite (CaF₂), a dosimetric material of large usage, exhibits both thermoluminescence (TL) and optically stimulated luminescence (OSL). In particular, the use of natural fluorite has extended to many places because of its abundance and low cost. This study investigates the TL and OSL signals of a natural fluorite sample from a mine in Boyacá-Colombia, stimulated using infrared (IR) and blue LEDs, and examines the relationship between these signals to optimize its potential for dosimetric applications. X-ray diffraction analysis was performed using a Bruker D8 Advance Eco X-ray diffractometer to confirm the crystalline structure of the material. Pellets were prepared by cold-pressing 40 mg of powdered samples, which were irradiated using a Co-60 gamma source (Gammacell 220 Nordion) at a dose of 500 Gy. TL spectra were obtained with a Hamamatsu optical spectrometer coupled to a hot planchet with a linear heating rate from 50 °C to 400 °C. The X-ray diffraction results confirmed that the material retained its CaF₂ structure after processing. The analysis revealed that only a subset of the defects responsible for the TL signal is optically active. Furthermore, the defects associated with the OSL response are completely depleted when the material is heated to 723 K. These findings indicate that the natural CaF₂ from Colombia can be utilized as a TL dosimeter even after OSL readout, making it suitable for applications such as personal dosimetry. These findings contribute to a better understanding of the TL properties of natural fluorite and its potential for dosimetric applications. Further studies are necessary to characterize sintered fluorite and assess its performance in practical dosimetry scenarios.

Presented author:
Ana Valeria Flores Esparza - Unidad Académica de Física de la Universidad Autónoma de Zacatecas

Authors:
1. Ana Valeria Flores Esparza, Unidad Académica de Física de la Universidad Autónoma de Zacatecas, Mexico. 2. Erick Campa Velázquez, Unidad Académica de Física de la Universidad Autónoma de Zacatecas, Mexico. 3. Dra. María Leticia Pérez Arrieta, Unidad Académica de Física de la Universidad Autónoma de Zacatecas, Mexico. 4. Dra. Carina Oliva Torres Córtes , Unidad Académica de Física de la Universidad Autónoma de Zacatecas, Mexico.

The growing dependence on ionizing radiation in fields such as medicine and industry requires precise systems for measuring absorbed dose. Among the most promising technologies is thermoluminescence, a phenomenon that certain materials such as hydroxyapatite (Hap) exhibit after being exposed to radiation. The Hap, in addition to being the main inorganic component of bone tissue, is biocompatible, making it ideal for applications in medical dosimetry. The addition of dopants such as europium (Eu^+3) improves its optical properties, increasing its sensitivity and effectiveness as a dosimetric material. Doping with Eu^+3 transforms Hap into a thermoluminescent sensor capable of detecting and quantifying X-ray doses with high precision. This is particularly relevant in medical environments where radiotherapy and diagnostic imaging require strict dose control to prevent collateral damage to healthy tissues. Previous studies have demonstrated that the thermoluminescent response of Hap significantly depends on factors such as dopant concentration and the structural conditions of the material, allowing its sensitivity to be adjusted according to specific needs. In this work, the thermoluminescent response of europium (Eu^+3)-doped hydroxyapatite synthesized via a hydrothermal method was analyzed. The samples were irradiated using an X-ray source designed and built in the laboratory, evaluating their luminescent behavior under different irradiation conditions. The results show that doping with Eu^+3 not only amplifies the thermoluminescent signal but also modifies the shape of the emission curves, with defined peaks correlated to variations in dopant concentration. This suggests optimal behavior within specific ranges, enabling its potential use in dosimetry. This study reinforces the potential of Hap as a versatile dosimeter for clinical and research applications. Its adaptability to different radiation environments makes it a valuable material for improving precision and safety in the management of ionizing radiations.

Presented author:
Abel Fernando Martínez Cruz - Universidad de Sonora

Authors:
1,*.-A. F. Martínez-Cruz, Departamento de Investigación en Polímeros y Materiales de la Universidad de Sonora, Hermosillo, Sonora, México 1.- V. R. Orante-Barrón, Departamento de Investigación en Polímeros y Materiales de la Universidad de Sonora, Hermosillo, Sonora, México 1.-C. Cruz-Vazquez, Departamento de Investigación en Polímeros y Materiales de la Universidad de Sonora, Hermosillo, Sonora, México 2.-R. Bernal, Departamento de Investigación en Física, Universidad de Sonora, Hermosillo, Sonora, México

MgO is a ceramic oxide with a wide bandgap (7.8 eV), low effective atomic number and high chemical stability (melting point = 2800 °C), which impacts researchers for exploring it as a dosimetric material [1]. There are few reports on luminescence dosimetry for undoped and doped MgO due to the lack of reproducibility for the luminescent signal in thermoluminescence (TL), regardless of the synthesis method (i. e. solid state reactions, crystal growth, hydrothermal synthesis, coprecipitation synthesis, and sol-gel) [2]. Solution combustion technique is particularly attractive due to its low cost and ability to obtain high-purity materials [2]. According to the antecedents mentioned above, thermoluminescence properties of annealed MgO chemically modified with Gd and Li, obtained by solution combustion (SCS), using glycine as fuel, are presented in this work for the very first time. Characteristic TL glow curves of MgO chemically modified with Gd and Li, annealed powder samples, after being exposed to beta radiation, were obtained, with a main peak located at ~ 360 °C. Moreover, the synthesized phosphor showed remarkable TL dosimetry properties according to the results obtained in this work: dose response without saturation evidence and a linear trend in the 0.5-16 Gy dose interval. The above-mentioned characteristics place MgO chemically modified with Gd and Li as a promising material for low and medium-dose applications. [1] Aayushi J., Pooja S., Shruti A., 2024. Synthesis, characterization and thermoluminescence of MgO: Li, Tb, Sm phosphor for high dose gamma dosimetry applications. [2] S. W. S. McKeever, M. Moscovitch and P. D. Townsend, Thermoluminescence Dosimetry Materials: Properties and Uses (Kent: NTP) (1995). ISBN 1 870965 19 1. [3] Barros V.S.M., Azevedo W. M., Khoury H. J., Cunha Filho P. L.

Presented author:
Malika Singhal - Physical Research Laboratory, Ahmedabad

Authors:
1. Malika Singhal, Physical Research Laboratory, Ahmedabad, 380009 and Indian Institute of Technology, Gandhinagar, Palaj, 382355, India 2. Souvik Mitra, Presidency University, Kolkata, 700003, India 3. Himela Moitra, Indian Institute of Technology, Kharagpur, 721302, India 4. Saibal Gupta, Indian Institute of Technology, Kharagpur, 721302, India 5. Aurovinda Panda, CSIR-National Geophysical Research Institute, Hyderabad 560007 6. Jayant Kumar Yadav, CSIR-National Geophysical Research Institute, Hyderabad 560007 7. Srinivasa Sarma, CSIR-National Geophysical Research Institute, Hyderabad 560007 8. Devender Kumar, CSIR-National Geophysical Research Institute, Hyderabad 560007 9. Naveen Chauhan, Physical Research Laboratory, Ahmedabad, 380009, India 10. Ashok Kumar Singhvi, Physical Research Laboratory, Ahmedabad, 380009, India

Jarosite is an anhydrous sulphate with a composition of AFe3(SO4)2(OH, H2O), where A is a metal. Past space missions identified Jarosite’s presence on the Martian surface, suggesting water-limited, acidic, and oxidizing conditions. We report the luminescence dosimetry properties of Jarosite for its use in dosimetry/geo-chronometry. Six natural Jarosite samples from Kachchh, India were analyzed for their thermoluminescence (TL), blue stimulated and infrared stimulated luminescence (BSL, IRSL) characteristics. Given that luminescence dosimetry/dating application requires preheating up to 300°C and that at elevated temperatures, Jarosite decomposes into yavapaiite, hematite, and D2O, further analysis of samples as received and their portions heated to 450℃ using Fourier transform infrared spectroscopy at IIT-Kharagpur and Cathodoluminescence-Xray Microprobe at CSIR-NGRI was carried out. No change on heating was seen, and reproducible TL yield under repeated readouts and irradiation cycles suggests Yavapaiite as the luminescence phase. Yavapaiite decomposes at 700℃. TL comprised four glow peaks between 100-350℃; the glow peak at 350℃ has an inferred mean life 0.3 of Myrs and a saturation dose of 1600Gy. BSL and IRSL signals were amenable to the Single Aliquot Regenerative (SAR) protocol with a saturation dose of 1800Gy and 1200Gy respectively. Athermal fading of g ~6 % per decade for all signals was seen. Results suggest that a simultaneous analysis of these signal can inform on short term variation in cosmic ray fluxes and date surface processes. K, U and Th measurements suggest an internal dose of ~1.6mGy/yr. With reported cosmic ray dose rate of 63 mGy/yr, these imply working age range of Jarosite as ~25 kyrs on Mars.

Presented author:
Anderson Bezerra Bezerra - IPEN

Authors:
1. Anderson M. B. Silva, Instituto de Pesquisas Energéticas e Nucleares/Comissão Nacional de Energia Nuclear, IPEN/CNEN, São Paulo, SP, Brazil 2. Daniel S. Rodrigues, Departamento de Física, Universidade Federal de Sergipe UFS, São Cristóvão, SE, Brazil 3.Danilo O. Junot, Instituto de Física Armando Dias Tavares, Universidade do Estado do Rio de Janeiro UERJ, Rio de Janeiro, RJ, Brazil 4.Patrícia L. Antonio, Instituto de Pesquisas Energéticas e Nucleares/Comissão Nacional de Energia Nuclear, IPEN/CNEN, São Paulo, SP, Brazil 5. Divanizia N. Souza,Departamento de Física, Universidade Federal de Sergipe UFS, São Cristóvão, SE, Brazil 6. Linda V. E. Caldas, Instituto de Pesquisas Energéticas e Nucleares/Comissão Nacional de Energia Nuclear, IPEN/CNEN, São Paulo, SP, Brazil

This study explores the luminescent properties of CaSO4:Dy,Mn, CaSO4:Tb,Mn, CaSO4:Tm,Mn, CaSO4:Yb,Mn, CaSO4:Eu,Mn and CaSO4:Ce,Mn composites synthesized via the slow evaporation route. Characterization of these materials was performed using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), and photoluminescence analysis. Their suitability for dosimetric applications was evaluated using Teflon-based pellets, incorporating thermoluminescence (TL) glow curve measurements with Schott BG-39 and Hoya U-340 bandpass filters to control wavelength response. Additionally, Continuous Wave Optically Stimulated Luminescence (CW-OSL) measurements were conducted to assess luminescence response. The different co-dopings resulted in significant variations in the emission curves, indicating changes in both intensity and shape. In the visible region, only the samples co-doped with ions such as Tb³⁺, Tm³⁺ and Dy³⁺, alongside manganese (Mn) and which have ionic radii closer to that of calcium (Ca²⁺ = 1.00 Å), exhibited peaks at higher temperatures. Conversely, in the UV region, significant peaks were exclusively observed in the Tm,Mn and Tb,Mn samples. These findings suggest that both types of samples are suitable for precise TL/OSL dosimetry due to minimal unwanted charge carrier release at elevated temperatures, enhancing accuracy and reliability in radiation dose measurements. The highest TL sensitivities were observed in the visible region for Tm,Mn, Dy,Mn, and Ce,Mn doped samples, and in the UV region for Tm,Mn, Ce,Mn, and Eu,Mn samples. A more in-depth dosimetric characterization was conducted, evaluating their reproducibility, linearity, fading, and the lower limit of detection. Overall, the evaluated dosimetric characteristics highlight the significant potential of these newly developed composites as TL/OSL detectors.

Poster session at the Amoxcalli Lobby - Facultad de Ciencias, UNAM
Jorge Altair Duarte-Rodríguez - Universidad de Sonora Thermoluminescent properties of commercial Himalayan salt grains subjected to beta radiation YSA
Alexia Oliveira Silva - Universidade de São Paulo THERMOLUMINESCENCE OF OLIVINE YSA
Yazmín Vicencio Hernández - IPN Thermoluminescent response of SrZrO3:Eu3+ beta irradiated YSA
Ana Victoria Tapia Gastélum - Universidad de Sonora Synthesis and thermoluminescence properties of ZnO:Tb YSA
Matheus Cavalcanti dos Santos Nunes - São Paulo State University - UNESP Unravel the optically stimulated luminescence of natural alexandrite YSA
Jun Hu - National Institutes for Quantum Science and Technology The development of AI-assisted track analysis system for CR-39 based space radiation dosimetry
Divanizia Souza - Universidade Federal de Sergipe, UFS DEVELOPMENT OF HIGH-SENSITIVITY CaSO4:Tm,Mn DETECTORS FOR THERMOLUMINESCENT AND OPTICALLY STIMULATED LUMINESCENT DOSIMETRY
Faycal Kharfi - Setif1 University-Ferhat Abbas Elaboration and OSL&TL response study of Na(0.1%) doped Al2O3 for radiation dosimetry application
Linda Caldas - IPEN SYNTHESIS AND INVESTIGATION OF THE LUMINESCENT PROPERTIES OF CaSO₄ DOPED WITH MANGANESE AND LITHIUM FOR APPLICATION IN RADIATION DOSIMETRY
Martin Autzen - RadPro International GmbH Dosimetric properties of the LCA OSL material for applications in personal dosimetry
Ilya Weinstein - Ural Federal University Thermally stimulated luminescence in UV irradiated InP/ZnS quantum dots
Makaiko Chithambo - Rhodes University The first of the sweet bananas: thermoluminescence of silica from banana stalks
Teodoro Rivera Montalvo - IPN Dosimetric characteristics of luminescent Detectors for Retrospective TL Dosimetry
Danilo O. Junot - UERJ Thermoluminescence and Optically Stimulated Luminescence in Crab Shell Biowaste Composites
Danilo O. Junot - UERJ Influence of Lithium Concentration on the TL/OSL Signals of CaSO4:Tm,Li Composites
VIVIANE ASFORA - UFPE Preparation of MgB4O7:Ce,Gd,Li for optically stimulated luminescence dosimetry
Viviane Asfora - UFPE Characterization of MgB4O7:Ce3+,Li+ for application in sterile insect technique dosimetry
William Jaramillo Garzón - Universidad Nacional de Colombia Study of the luminescence response of a Colombian natural fluorite
Carolina Castilho - USP Development of LiCaAlF6:Sm nanoparticles for application in RPL dosimetry
Carlos Gonzales Lorenzo - Universidad Nacional de San Agustin Thermoluminescent, structural, and optical properties of undoped and Eu-, Ce-, Tb-, Sm-, Cu-, Mn-, and Li- doped MgSiO3 phosphors, synthesized by sol-gel combustion technique
Alejandra Inzunza Lugo - IPN Optimización de la Gestión de Calidad en Radioterapia Mediante Dosimetría Matematica
Isabela Alves Ferreira - University of Sao Paulo - USP A first look at phototransferred thermoluminescence of rose quartz
Nancy Gabriela Chicango Arcos - USP-RP Scintillating LiCaAlF6:Eu nanoparticles for application in ionizing radiation dosimetry
Ana Valeria Flores Esparza - Unidad Académica de Física de la Universidad Autónoma de Zacatecas Thermoluminescent Response of Hydroxyapatite (Hap) Doped with Europium (Eu^3+) to Gamma Radiation
Abel Fernando Martínez Cruz - Universidad de Sonora Thermally Stimulated Luminescence of Chemically Modified Magnesium Oxide with Gd3+ and Li+, Obtained by a Glycine-based Combustion Process
Malika Singhal - Physical Research Laboratory, Ahmedabad Radiation Dosimetric characterization of Jarosite: a Martian analog from Kachchh India
Matheus Cavalcanti dos Santos Nunes - São Paulo State University - UNESP Investigation of the luminescence of laser-sintered Al2O3-based synthetic ceramics
Isabela Alves Ferreira - University of Sao Paulo - USP OPTICALLY STIMULATED LUMINESCENCE OF LUNAR REGOLITH SIMULANT: OPRH3WO
Anderson Bezerra Bezerra - IPEN ANALYSIS OF LUMINESCENT AND DOSIMETRIC PROPERTIES OF CaSO₄:RE,Mn (RE = Dy, Tb, Tm, Yb, Eu, Ce) PHOSPHORS SYNTHESIZED BY THE SLOW EVAPORATION METHOD
Sophia Welti - Hiroshima University Using a portable colorimeter for dose estimate using radiochromic PVA-I-Si gel (PAISiN) for field applications
Meza Ruiz Humberto Eduardo - UNISON Thermally Stimulated Luminescence of NaF and NaF:Dy Phosphors Exposed to Beta Particle Radiation
Cristian Eduardo Bracamonte Estrada - Universidad de Sonora Thermoluminescence of beta-particle irradiated SrZrO3
Perla Rodríguez Ortega - UAZ Thermoluminescent Response in ZnS and ZnS:Mn Nanoparticles Exposed to X-rays
Gibrán Alberto Mendívil Islas - UNISON Thermoluminescence of ZnO:Tm exposed to beta particle irradiation

Wednesday June 11, 2025

Presented author:
Francesca Barco - Università di Pisa

Authors:
1. -Tommaso Butini, Department of Biological, Chemical, and Pharmaceutical Sciences and Technologies “STEBICEF”, University of Palermo, Palermo, Italy. 2. -Corresponding Authors: Francesca Barco, School of Engineering, University of Pisa, Pisa, Italy. 3.- Mariagrazia Quattrocchi, Department of Radiology, St. Luca Hospital, Lucca, Italy. 4.- Riccardo Ciolini, School of Engineering, University of Pisa, Pisa, Italy. 5.- Maurizio Marrale, Department of Physics and Chemistry “Emilio Segrè”, University of Palermo, Palermo, Italy. 6.- Maria Grazia Cascone, School of Engineering, University of Pisa, Pisa, Italy. 7.- Elisabetta Rosellini, School of Engineering, University of Pisa, Pisa, Italy. 8.- Magno Nogueira Xavier, Departamento de Física, Universidade Federal de Sergipe, São Cristóvão-SE, Brazil. 9.- Susana de Souza Lalic, Departamento de Física, Universidade Federal de Sergipe, São Cristóvão-SE, Brazil. 10.- Francesco d'Errico, School of Engineering, University of Pisa, Pisa, Italy.

The increasing concern about radiation exposure from various sources, including nuclear accidents and medical treatments, underscores the need for effective biodosimetry and radioprotection strategies. This study explores the biological response of the plant model Allium cepa to different types of ionizing radiation, including X-rays and electrons, and varying dose rates. The use of Allium cepa as a plant model is particularly promising due to its high sensitivity to radiation, making it an effective and low-cost tool for investigating radiation-induced damage. Our research aims to understand the relationships between absorbed dose, radiation type, and dose rate. We analyzed the genotoxicity and cytotoxicity of these radiations using the micronucleus test and mitotic index monitoring. Preliminary analyses support the applicability of a linear-quadratic model, incorporating a cell-killing term, to describe the biological response. Our findings suggest a possible initial curvature in the dose-response curve, followed by the onset of lethal effects at higher doses. This study has significant implications for the development of biodosimetry tools and radioprotection strategies. The use of Allium cepa as a plant model offers a promising approach for assessing radiation exposure and understanding the underlying biological mechanisms. Our research contributes to the ongoing efforts to enhance radiation safety and protection, ultimately benefiting both medical and occupational settings.

Presented author:
Alban Roussel - IRSN

Authors:
1.- ROUSSEL Alban, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), France 2.- L’HOMME Bruno, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), France 3.- TROMPIER François, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), France 4.- GRUEL Gaëtan, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), France 5.- DOS SANTOS Morgane, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), France

In case of radiological accidents, EPR spectroscopy technique is employed for retrospective dosimetry. This method is especially used for bone dose estimation in cases of localized overexposures. However, bone sampling can be performed several days or months after exposition leading to an uncertainty on the real absorbed dose on the day of exposition due to bone physiology and remodeling. A preclinical study conducted with 80 kV X-rays showed no dose-effect impact on both bone dose and decrease of EPR signal with time. Our study aims to determine the impact of X-ray quality on the absorbed dose to the bone and the EPR signal at different time points by EPR spectroscopy. Localized paw exposures of C57Bl6/j mice were performed at 30 Gy (Kair) with four voltages: 50 kV, 80 kV, 220 kV, and 10 MV. Irradiated tibias were collected for EPR spectroscopy analysis at 0, 14, 21, 42, 84, 168 days. EPR measurements were performed with the Bruker Magnettech ESR 5000 X-band spectrometer. The additive dose method was used to estimate the absorbed dose in bones. EPR measurements estimate an initial bone dose (D0) of 151.2 ± 15.0 Gy, 104.3 ± 8.0 Gy, and 36.1 ± 11.6 Gy for 50 kV, 220 kV, and 10 MV expositions respectively (211.3 ± 22.1 Gy for 80 kV). EPR signals decrease other time, with similar trends observed for 50 kV and 80 kV groups (approximately -27% at D21 and -42% at D84). The 220 kV group shows a quicker decrease (-48% at D21, -52% at D84). 10 MV decrease is much quicker (-80% at D21, -100% at D84). The absorbed bone dose depends on the X-ray quality, which is related to the predominance of the photoelectric effect. EPR measurements are currently being conducted for bones collected at other time points to better characterize signal evolution.

Presented author:
ILIA FILIPEV - Centre for Medical Radiation Physics, University of Wollongong

Authors:
1. Ilia Filipev, Centre for Medical Radiation Physics, University of Wollongong, NSW, Australia. 2. Nicholas Hardcastle, Department of Physical Sciences, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia; Centre for Medical Radiation Physics, University of Wollongong, NSW, Australia; Sir Peter MacCallum Department of Oncology, University of Melbourne, Melbourne, VIC, Australia. 3. Craig Davis, Faculty of Engineering and Information Sciences, University of Wollongong, NSW, Australia. 4. Giordano Biasi, Centre for Medical Radiation Physics, University of Wollongong, NSW, Australia. 5. Martin Carolan, Illawarra Cancer Care Centre, Illawarra Shoalhaven Local Health District, Wollongong, NSW, Australia. 6. Saree Alnaghy, Nelune Comprehensive Cancer Centre, Prince of Wales Hospital, Randwick, NSW, Australia; Centre for Medical Radiation Physics, University of Wollongong, NSW, Australia. 7. Justin B Davies, Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW, Australia. 8. Dean Cutajar, Centre for Medical Radiation Physics, University of Wollongong, NSW, Australia. 9. Bradley M. Oborn, Centre for Medical Radiation Physics, University of Wollongong, NSW, Australia; Illawarra Cancer Care Centre, Illawarra Shoalhaven Local Health District, Wollongong, NSW, Australia; Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiooncology-OncoRay, Dresden, Germany. 10. Joel Poder, St George Hospital Cancer Care Centre, Kogarah, NSW, Australia; Centre for Medical Radiation Physics, University of Wollongong, NSW, Australia. 11. Michael Lerch, Centre for Medical Radiation Physics, University of Wollongong, NSW, Australia. 12. Susanna Guatelli, Centre for Medical Radiation Physics, University of Wollongong, NSW, Australia. 13. Marco Petasecca, Centre for Medical Radiation Physics, University of Wollongong, NSW, Australia. 14. Tomas Kron, Department of Physical Sciences, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia; Centre for Medical Radiation Physics, University of Wollongong, NSW, Australia; Sir Peter MacCallum Department of Oncology, University of Melbourne, Melbourne, VIC, Australia. 15. Anatoly Rosenfeld, Centre for Medical Radiation Physics, University of Wollongong, NSW, Australia.

Accurate dose verification in steep-gradient regions is critical for advanced radiation therapy such as stereotactic X-ray modalities. Time-resolved dose verification for complex clinical plans will open new opportunities for error identification. MagicPlate-976 (MP976), a next-generation 2D monolithic pixelated silicon detector developed by the Centre for Medical Radiation Physics, addresses these needs by offering high spatial and temporal resolution without the need for external triggering. This work combines the system’s characterisation for small-field dosimetry with its application for patient-specific QA for vertebral stereotactic ablative body radiotherapy (SABR) in the axial plane. The MP976 detector consists of 976 ion-implanted diodes on a thin n-type epitaxial silicon substrate with a total array area of 58x58 mm2. Diodes in the central region (20x20 mm2) have 1mm pitch, and 2mm in the peripheral region. The system has zero dead time and allows setting the integration time down to 0.2 ms (5 kHz sampling). The detector was tested under clinical X-rays and demonstrated dose stability and linearity; the variations in response due to dose-per-pulse and beam incidence angle were characterised. The output factors, depth dose and beam profiles were validated against reference data and showed agreement within clinically acceptable tolerances. Using MP976 with specialised phantom for the axial plane measurements (VERTA-mp system), four vertebral SABR plans of various complexity were measured and compared with Eclipse TPS (AcurosXB, dose to medium) and Gafchromic EBT4 films. The results showed 2D-gamma pass rates (5%/1mm) above 94.4% when compared to TPS and above 96.5% compared to EBT4. 90%/25% ratios for anterior-posterior profiles of the high-gradient region matched within the uncertainties. The new MagicPlate-976 detector system is shown to be suitable for dosimetry in small fields and steep dose gradients with potential to substitute films in patient-specific QA and its applications extending to time-resolved verification and error identification in complex radiotherapy plans.

Presented author:
Mads Lykke Jensen - Paul Scherrer Institute

Authors:
Mads Lykke Jensen, Department of Radiation Safety and Security, Paul Scherrer Institute, Villigen PSI, Switzerland Jeppe Brage Christensen, Department of Radiation Safety and Security, Paul Scherrer Institute, Villigen PSI, Switzerland Michele Togno, Center for Proton Therapy, Paul Scherrer Institute, Villigen PSI, Switzerland Federico Alejandro Geser, Department of Radiation Safety and Security, Paul Scherrer Institute, Villigen PSI, Switzerland Malgorzata Makowska, Department of Radiation Safety and Security, Paul Scherrer Institute, Villigen PSI, Switzerland Eduardo Yukiharaa, Department of Radiation Safety and Security, Paul Scherrer Institute, Villigen PSI, Switzerland

Linear energy transfer (LET) is known to be linked to the relative biological effectiveness (RBE) of proton radiotherapy. Significant efforts are invested in incorporating LET into treatment planning systems, aiming to utilize this proxy for RBE to increase the overall radiotherapeutic outcomes. Nevertheless, most dosimetry systems exhibit an under-response in high-LET regions, making experimental validation of LET-optimized treatment plans challenging. In this contribution, we present a novel dosimetry system based on optically stimulated luminescence (OSL), capable of measuring dose and LET simultaneously in 2D, offering a promising solution for, e.g., experimentally validating LET-optimized radiotherapy. Al₂O₃:C films were irradiated with X-rays and protons and read out using a custom-built OSL reader. The reader consists of an XY-stage, a pulsed LED for stimulation, and a photomultiplier tube along with appropriate filters and optics for the detection. The pulsed readout enabled the decomposition of the OSL signal into the two spectral components characteristic of Al₂O₃:C, the ratio of which has been demonstrated to correlate with the LET. We achieved a minimum detectable dose of 3 mGy within 1 mm² spots and demonstrated a precision of 3% after a 350 mGy homogeneous irradiation with X-rays. Readouts from a proton-irradiated film demonstrated high-precision LET mapping, with LET values increasing toward the Bragg peak and peaking in the distal fall-off region. This novel system enables simultaneous retrieval of dose and LET information in 2D from Al₂O₃:C films, providing a promising tool for validating LET-optimized treatment planning in proton therapy.

Presented author:
Iván D. Muñoz - German Cancer Research Center

Authors:
1. I. D. Muñoz, Department of Radiation Oncology, Heidelberg University Hospital (UKHD), Heidelberg, Germany and Division of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany 2. J. B. Christensen, Department of Radiation Safety and Security, Paul Scherrer Institute (PSI), Villigen PSI, Switzerland 3. D. García-Calderón, Division of Biomedical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany 4. J. Seco, Division of Biomedical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany 5. E. G. Yukihara, Department of Radiation Safety and Security, Paul Scherrer Institute (PSI), Villigen PSI, Switzerland 6. O. Jäkel, Division of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany and Heidelberg Ion-Beam Therapy Center (HIT), Department of Radiation Oncology, Heidelberg University Hospital (UKHD), Heidelberg, Germany

The linear energy transfer (LET) is a key parameter describing ionization density in proton and ion-beam therapy. Clinically, LET is often used as a physical quantity to predict the relative biological effectiveness (RBE). However, no experimental tools are currently available to measure these quantities within a clinical context. In this work, we developed tools to accurately measure LET and estimate the RBE of protons and heavier ions using Al2O3:C,Mg-based fluorescent nuclear track detectors (FNTDs) and optically stimulated luminescent detectors (OSLDs). FNTDs and OSLDs were calibrated through irradiation with monoenergetic protons, 4He-, 12C-, and 16O-ions with known LET values. For FNTDs, a robust protocol was developed to correct for sensitivity variability among individual detectors. Additionally, phenomenological RBE models were integrated for both FNTD and OSLD workflows to estimate the RBE from the measured LET. Measurements in proton and 4He ion spread-out Bragg peaks (SOBPs) were conducted at different positions along the central beam axis to test the proposed methods. Monte Carlo simulations and cell survival clonogenic assays were performed to validate LET and RBE values, respectively. Comparing the detector results against simulations, we found that both FNTDs and OSLDs can measure track- and dose-averaged LET with an accuracy of 12% and 17%, respectively. For RBE estimation, the detectors results agreed with cell experiment outcomes within 10%. Major deviations between validation data and the proposed methods were observed at the distal dose fall-off in the SOBPs, attributed to the sharp gradients in this region and limited calibration data for higher LET values. Ongoing research explores the feasibility of calculating microdosimetric quantities from LET measurements to predict RBE using the microdosimetric kinetic model. Acknowledgements: IDM and DG-C acknowledge funding from the German Academic Exchange Service (DAAD). JBC and EGY acknowledge partial support from the Swiss National Science Foundation.

Presented author:
Cristiana Magalhães Correia Rodrigues - Laboratório de Instrumentação e Física Experimental de Partículas (LIP)

Authors:
1. Cristiana Rodrigues, Laboratório de Instrumentação e Física Experimental de Partículas (LIP), Faculdade de Ciências. Universidade de Lisboa (FCUL), Centro de Ciências e Tecnologias Nucleares (C2TN). Departamento de Engenharia e Ciências Nucleares (DECN). Instituto Superior Técnico (IST), Portugal 2. Ana Luísa Rodrigues, Centro de Ciências e Tecnologias Nucleares (C2TN). Departamento de Engenharia e Ciências Nucleares (DECN). Instituto Superior Técnico (IST), Portugal 3. José Vedelago, Department of Radiation Oncology, Heidelberg University Hospital (UKHD) and Division of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Germany 4. João Gentil Saraiva, Laboratório de Instrumentação e Física Experimental de Partículas (LIP), Portugal 5. António Pereira Gonçalves, Centro de Ciências e Tecnologias Nucleares (C2TN). Departamento de Engenharia e Ciências Nucleares (DECN). Instituto Superior Técnico (IST), Portugal 6. Luís Peralta, Laboratório de Instrumentação e Física Experimental de Partículas (LIP), Faculdade de Ciências. Universidade de Lisboa (FCUL), Portugal

Understanding the intricate effects of radiation at the microscale is pivotal for advancing cancer treatment strategies. The groundbreaking nature of ion therapy requires new developments in dosimetry to access a more detailed description of the energy distribution inside the cells and contribution from the different secondary particles. Optically stimulated luminescence detectors (OSLDs) have been gaining interest for in vivo dosimetry in radiobiology. Fluorescent Nuclear Track Detectors (FNTDs) also show promise, offering high-resolution particle interaction mapping. However, the current FNTD crystal composition shows limited sensitivity to low-mass particles, neutrons and photons. This study focuses on the development of novel passive dosimeters with enhanced microscale sensitivity for radiobiology. Corundum (Al2O3) single crystals, the matrix of a FNTD, were grown using the flux method, with a Li2O–MoO3 flux system. The continuous wave optically stimulated luminescence (CW-OSL) of flux-grown undoped and doped Al2O3 crystals was investigated. Standard (C and C,Mg) and novel doping combinations, namely carbon co-doping with Zn, Ti(IV) and Mn(II), were explored. The samples were exposed to a dose of 90Sr/90Y beta radiation between 6.2 Gy and 62 Gy. All materials had a linear response in the studied dose range. C,Ti co-doping presented the highest signal, showing promise for OSL applications. The effect of material purity used for crystal growth on the OSL was investigated. Higher-purity samples presented higher OSL sensitivity. Nevertheless, the higher-purity Al2O3:C,Mg showed an OSL sensitivity 12 times lower than that of the commercial Al2O3:C,Mg. To evaluate the potential of these materials as FNTDs, carbon ion irradiation experiments were conducted at the Heidelberg Ion Beam Therapy Center (HIT; Germany). Preliminary results revealed visible carbon ion tracks in the higher-purity samples (undoped and doped), indicating that these crystals could be effective FNTDs. Further work will focus on investigating the sensitivity of the grown materials to other particle types.

Presented author:
Caroline Fernandes - University of Sao Paulo

Authors:
1. Caroline Paschoal Fernandes, University of Sao Paulo, Brazil 2. Go Okada, Kanazawa Institute of Technology, Japan 3. Sonia Hatsue Tatumi, University of Sao Paulo, Brazil 4. Rene Rojas Rocca, Federal University of Sao Paulo, Brazil

Although several types of glass have been explored for their luminescent properties, research on sodium borate glass, particularly Ag-activated, remains limited. Therefore, the aim of this study is to investigate radiophotoluminescence (RPL), optically stimulated luminescence (OSL) and thermoluminescence (TL) properties of the latter glass material for, particularly, dosimetric applications. The samples were synthesized using the melt-quenching technique. The reagents used were sodium borate decahydrate (Na₂O·2B₂O₃) and AgNO₃ at concentrations 0.0, 0.5, 1.0, 1.5, 2.0, and 2.5 wt%. Luminescence analysis was conducted using the TSL/OSL/RPL Automated and Integrated Measurement System (TORAIMS). Additional measurements were made by using Risø TL/OSL-DA-20. Concentration of Ag showing the highest sensitivity varies by luminescence phenomenon. For TL, OSL, and RPL, samples doped with 0.0, 0.5, and 2.0% Ag showed the highest sensitivity, respectively. For TL and OSL, the sensitivity is determined both by the radiative recombination efficiency of luminescent centers and by the number of charges stored per dose at charge-trapping centers. However, the difference is the way to release the trapped charges: heat for TL and light for OSL. The present result suggests that higher Ag concentrations negatively impact these factors, both for OSL and TL sensitivity. In contrast, RPL sensitivity depends on the number of charges captured by RPL center precursors and the efficiency of the luminescent center formed as RPL, in which higher doping levels improve in the present material. Furthermore, a study of annealing, at different temperatures and times, was carried out to verify its influence on the luminescence response for TL, OSL and RPL. Additional discussion about dosimetric properties such as dose response, fading, reproducibility and photoluminescence lifetime of the samples will be also presented.

	ABC auditorium - Facultad de Ciencias, UNAM
08:30 - 09:00	Registration
09:00 - 09:30	Invited Talk 5 Susana de Souza Lalic - Universidade Federal de Sergipe "Plant Stem Cells as an Ethical Alternative for Biodosimetry"
09:30 - 10:00	Dose Reconstruction and Dating I Moderators: Francesco D'Errico & Regina DeWitt
09:30 - 09:45	Francesca Barco - Università di Pisa "Investigating the Biological Response of Allium cepa to Ionizing Radiation: Implications for Biodosimetry and Radioprotection"
09:45 - 10:00	Alban Roussel - IRSN "Kinetics of radio-induced free radicals in mouse bone for retrospective dose estimation by EPR spectroscopy: impact of X-ray quality"
10:00 - 10:30	Coffee break
10:30 - 12:00	Young Scientist Award Session Moderators: Oswaldo Baffa Filho & Monika Rani
10:30 - 10:45	ILIA FILIPEV - Centre for Medical Radiation Physics, University of Wollongong "Time-Resolved High Spatial Resolution Dosimetry for Stereotactic Radiotherapy Using “MagicPlate-976”: A Novel Trigger-Less Pixelated Silicon Detector with Non-Uniform Diode Arrangement"
10:45 - 11:00	Mads Lykke Jensen - Paul Scherrer Institute "High-resolution mapping of LET and dose in 2D"
11:00 - 11:15	Iván D. Muñoz - German Cancer Research Center "Assessment of the linear energy transfer and relative biological effectiveness with Al2O3:C,Mg luminescent detectors"
11:15 - 11:30	Jacob Christian Warming - Aarhus University, Department of Physics and Astronomy "A pulsed-laser approach to the determination of OSL cross sections and trap depths"
11:30 - 11:45	Cristiana Magalhães Correia Rodrigues - Laboratório de Instrumentação e Física Experimental de Partículas (LIP) "Novel Flux-Growth of Al₂O₃-based Luminescent Dosimeters"
11:45 - 12:00	Caroline Fernandes - University of Sao Paulo "Luminescence properties of Ag-activated sodium borate glass"
12:00 - 18:00	Bus to Teotihuacan site and lunch

Thursday June 12, 2025

Presented author:
Linh Tran - Centre for Medical Radiation Physics, University of Wollongong

Authors:
1. Linh T. Tran, Centre for Medical Radiation Physics (CMRP), University of Wollongong, Wollongong, Australia 2. Vladimir Pan, Centre for Medical Radiation Physics (CMRP), University of Wollongong, Wollongong, Australia 3. James Vohradsky, Centre for Medical Radiation Physics (CMRP), University of Wollongong, Wollongong, Australia 4. Marco Petasecca, Centre for Medical Radiation Physics (CMRP), University of Wollongong, Wollongong, Australia 5. Michael Lerch, Centre for Medical Radiation Physics (CMRP), University of Wollongong, Wollongong, Australia 6. Marco Povoli, SINTEF, Norway 7. Angela Kok, SINTEF, Norway 8. Dirk Wagenaar, Proton Therapy Centre, University Medical Center Groningen, Netherlands 9. Stefan Both, Proton Therapy Centre, University Medical Center Groningen, Netherlands 10. Taku Inaniwa, National Institutes for Quantum Science and Technology, Japan 11. Nicholas Depauw, Massachusetts General Hospital, Boston, USA 12. Anatoly B. Rosenfeld, Centre for Medical Radiation Physics (CMRP), University of Wollongong, Wollongong, Australia

Over the last 25 years, the Centre for Medical Radiation Physics, University of Wollongong has successfully developed a microdosimetric probe MicroPlusTM which is based on a silicon on insulator (SOI) microdosimeter with 3D micron sized sensitive volumes (SVs) array mimicking dimensions of cells, known as the “Bridge” and “Mushroom” microdosimeters, for relative biological effectiveness (RBE) prediction in particle therapy, boron neutron capture therapy and fast neutron therapy [1, 2]. Several designs of high definition 3D SVs fabricated at SINTEF, Norway using 3D MEMS technology were implemented. SVs were segmented into sub-arrays to reduce capacitance and avoid pile up in high dose rate pencil beam scanning applications. Each new generation has their SV definition significantly improved. The MicroPlusTM probe was successfully utilised to verify the proton LETd-optimised treatment plan on ependymoma structure at Massachusetts General hospital (MGH). A clear reduction in the dose mean lineal energy, (yD), was found within the brainstem by an average of ~12% while maintaining adequate coverage of the tumour structure [3]. The MicroPlusTM probe was also used to evaluate the RBE of various ions [4] and for validation of treatment planning system in multiple ion therapy combining He, C, O and Ne ion beams [5]. Excellent agreement of predicted, based on measured dose mean lineal energy (yD), and measured cell surviving fraction in proton and ion therapeutic beams has been demonstrated. Presentation will overview applications of MicroPlusTM in different clinical scenarios including introduction of a new version of the compact MicroPlusTM2 for routine LETd and RBE-weighted dose QA in a clinical setting. References: [1] Rosenfeld A. “Novel detectors for silicon based microdosimetry, their concepts and applications”, Nucl. Instrum. Methods., Phys. Res. A 809, 156–170, February 2016 [2] Linh T. Tran et. al., “Thin Silicon Microdosimeter utilizing 3D MEMS Technology: Charge Collection Study and its application in mixed radiation fields”, IEEE Transactions on Nuclear Science, Volume: 65, Issue: 1, 467-472, Jan. 2018. [3] Pan V. et al “LETd Optimization verification with an SOI microdosimeter”, Int J Radiat Oncol Biol Phys . 2024 Jul 1;119(3):946-956. doi: 10.1016/j.ijrobp.2023.12.036. Epub 2024 Jan 31. [4] Linh T. Tran, et. al., “The relative biological effectiveness for carbon, nitrogen and oxygen ion beams using passive and scanning techniques evaluated with fully 3D silicon microdosimeters” Medical Physics, 2018, DOI10.1002/mp.12874. [5] Lee et al., “Estimating the biological effects of helium, carbon, oxygen, and neon ion beams using 3D silicon microdosimeters”, Phys. Med. Biol. 66 045017 2021.

Presented author:
Jeppe Brage Christensen - Paul Scherrer Institute (PSI)

Authors:
Jeppe Brage Christensen, PSI, Switzerland Ivan Domingo Munoz, DKFZ, Germany Mads Lykke Jensen, PSI, Switzerland Lily Bossin, PSI, Switzerland Oliver Jäkel, DKFZ, Germany Eduardo Gardenali Yukihara, PSI, Switzerland

Optically stimulated luminescence detectors (OSLDs) have been used for dosimetry and radiation quality assessment in ion beams for nearly two decades. Their ability to assess both dose and linear energy transfer (LET) in sub-mm³ detector volumes makes them valuable in ion beam therapy, as radiation quality determinations allow for corrections of ionization-quenched responses. The determination of dose and LET subsequently enables an assessment of the relative biological effectiveness (RBE) in proton and helium ion beam therapy using e.g. the McNamara and Mairani RBE models. Here, we aim to demonstrate the first simultaneous estimates of dose, LET, and RBE with a single OSLDs in both proton and helium ion beam therapy. To achieve this, OSLDs were irradiated along the central beam axis of two proton and helium ion beam spread-out Bragg peaks (SOBPs). The OSLD dosimetry was validated by ionization chamber measurements. To validate the radiation quality measurements, Monte Carlo simulations were employed to score different LET averages. Results showed good agreement between OSLD and ionization chamber dose measurements, within uncertainties (k = 2). LET assessments are found to be most accurate for fluence-averaged LET, within 10 %. However, the RBE models rely on dose-averaged LET as input for RBE estimations. The OSLD-derived RBE values matched those from cell survival clonogenic assays conducted in a previous work, except at the steep dose and LET gradients close to the distal edge of the SOBPs, where discrepancies were observed for helium ions. These findings demonstrate the OSLDs' ability to simultaneously assess dose, LET, and RBE in proton and helium ion therapy under reference conditions. Future work will focus on in-field measurements, potentially with OSLDs in anthropomorphic phantoms, to further evaluate RBE models in clinical settings.

Presented author:
Olivier Van Hoey - SCK CEN

Authors:
1. Olivier Van Hoey, Belgian Nuclear Research Center (SCK CEN), Mol, Belgium 2. Marijke De Saint-Hubert, Belgian Nuclear Research Center (SCK CEN), Mol, Belgium 3. Liliana Stolarczyk, Danish Centre for Particle Therapy, Aarhus University Hospital, Aarhus, Denmark 4. Paweł Olko, Institute of Nuclear Physics, Polish Academy of Sciences (IFJ PAN), Kraków, Poland

Although proton therapy strongly decreases out-of-field doses in comparison with conventional radiotherapy, out-of-field doses are still an important consideration, especially for pediatric and pregnant patients. These doses can be assessed by Monte Carlo radiation transport simulations and analytical models and validated by in-phantom measurements. For in-phantom measurements the question remains how different detector types can be combined to assess the total out-of-field dose due to all field components, including neutrons. In previous studies lithium fluoride (LiF) based thermoluminescent detectors (TLDs) and BD-PND bubble detectors were successfully characterized for all the relevant radiation types. The goals of this work were to investigate the typical contributions of the different radiation types to the out-of-field doses in proton therapy, model the responses of LiF TLDs and BD-PND bubble detectors and provide recommendations for combining both detector types to assess the total out-of-field dose. This study looked back on a EURADOS Working Group 9 measurement campaign performed in 2014 at the CCB Krakow proton therapy facility, where a 5-year-old phantom was treated for a brain tumor. This experiment was mimicked by simplified MCNP6.2 Monte Carlo simulations. The simulations were in acceptable agreement with the measurements, considering the simplifications. Based on this study it is recommended to assess the out-of-field absorbed dose in water from the non-neutron component by MTS-7 TLDs with an expected slight overestimation by about 5% or by the more sensitive MCP-7 TLDs with an expected underestimation by about 20%. The total out-of-field dose equivalent from all components can be estimated by combining the absorbed dose from the MTS-7 or MCP-7 TLDs with a quality factor Q=1 for the non-neutron component with the BD-PND bubble detector dose equivalent for the neutron component with an expected slight underestimation by about 20%.

Presented author:
Jacob Johansen - Aarhus University Hospital

Authors:
1. JG Johansen - Department of Clinical Medicine, Aarhus University, Aarhus, Denmark and Danish Centre for Particle Therapy, Aarhus University Hospital, Aarhus, Denmark 2. LB Nørregaard - Department of Physics and Astronomy, Aarhus University, Aarhus, Denmark 3. HL Riis - Department of Oncology, Odense University Hospital, Odense, Denmark and Department of Clinical Research, University of Southern Denmark, Odense, Denmark

Introduction and aim The MR-linac is a combined X-ray (6MV) unit and Magnetic Resonance (MR) scanner. It offers high-resolution images during treatment. The strong magnetic field from the MR scanner also complicates the dosimetry, as ionization chambers are affected by the magnetic field. An alternative dosimeter type is the electrically passive scintillator. Several studies with fiber-coupled organic point scintillators have been performed with positive results. Studies on Inorganic scintillators are sparser despite the higher light yield, due to the non-water equivalence. The aim of this study is to test an inorganic scintillator detector on an MR-linac. Percentage depth dose curves and output factors are measured with an in-house developed inorganic scintillator detector and compared to diamond detector measurements and Monte Carlo simulations. Material and Method The detector consisted of a 0.5x0.5x0.5 mm3 ZnSe:O crystal coupled to a 15 m long optical fiber. The optical fiber was then connected to a Si-diode, which recorded the light signal with a 20Hz sample rate. All measurements were done in a water phantom. The detector’s dose-rate linearity was tested by irradiating with varying pulse repetition frequencies. The percentage depth dose curve was determined for a 10x10 cm2 and 2x2 cm2 field at 10 cm depths using both the scintillator and a microDiamond detector. The output factors were determined in fields ranging from a 1x1 cm2 to a 22x22 cm2. Results The detector showed dose rate linearity in the entire studied range. After accounting for the non-water equivalence, the percentage depth dose curves of the scintillator, diamond and Monte Carlo simulation agreed within 2%. Larger variation was seen in the output factors for small fields. Conclusion Inorganic-scintillator based point detectors offer time-resolved dosimetry with a high signal-to-noise ratio. The detector provides measurement accuracies comparable to current state-of-the-art detectors with no significant impact of the magnetic field.

Presented author:
Morgane Dos Santos - IRSN

Authors:
1.- DOS SANTOS Morgane, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), France 2.- ROUSSEL Alban, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), France 3.- L’HOMME Bruno, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), France 4.- TROMPIER François, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), France 5.- GRUEL Gaëtan, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), France

Preclinical imaging systems have become an essential tool for biology, medicine, and radiobiology research, enabling anatomical, morphological, functional, and molecular analyses. In recent years, many imaging techniques used in clinical practice have been adapted to small animals, allowing to monitor and quantify a treatment's impact or radiation's effect on an organ or tissue. In particular, more and more laboratories are equipping with microCT in vivo and non-invasive imaging systems for longitudinal monitoring, enabling to follow the evolution of pathology over time for the same animal. Although this imaging system has many advantages, it relies on the use of low-energy X-rays, and the dose absorbed by the various tissues during acquisitions must not be overlooked. To achieve the dose absorbed by the different tissues, we performed an experimental and numerical study on the microCT system available in our lab. Experimental measurements consisted in estimating the tissue dose using EBT3 radiochromic films, ionization chamber and alanine pellets. The bone dose was also assessed by EPR spectroscopy using bone samples taken from mice. In parallel, Monte Carlo simulations were performed with Geant4 to obtain the 3D distribution of dose. Experimental measurements for tissue dose estimation showed good agreement between the techniques and the manufacturer's data (mean dose rate of 0.210 Gy/min ± 6.1%). Experimental estimation of the dose to bone showed that it is 7 times greater than the dose to tissue, as expected for low-energy X-rays where dose deposition is mainly due to the photoelectric effect. This interaction is highly dependent on material density (with a Z3 dependence) leading to significant heterogeneity in the dose deposition (Dbone >> Dtissue). Monte Carlo simulations are already underway, but our first results showed good agreement with experimental data with a factor 7 between the bone and tissue doses.

Presented author:
Eike Hohmann - Paul Scherrer Institute

Authors:
E. Hohmann, Department of Radiation Safety and Security, Paul Scherrer Institute, Villigen M. Bolzonella, Department of Radiation Safety and Security, Paul Scherrer Institute, Villigen R. Galeev, BKW Energie AG, Mühleberg, Switzerland L. Pedrazzi, Department of Radiation Safety and Security, Paul Scherrer Institute, Villigen M. Tisi, Department of Radiation Safety and Security, Paul Scherrer Institute, Villigen D. Zeitz, Department of Radiation Safety and Security, Paul Scherrer Institute, Villigen S. Harzmann, Department of Radiation Safety and Security, Paul Scherrer Institute, Villigen S. Mayer, Department of Radiation Safety and Security, Paul Scherrer Institute, Villigen

Passive neutron dosemeters used for dose monitoring of occupationally exposed workers or places adjacent to controlled areas are routinely calibrated in fields produced by radioisotope sources. Radiation fields around high-energy particle facilities or at high altitudes often contain a significant component of neutrons with energies of more than 20 MeV. Reference fields with a high-energy neutron component are desirable for the calibration of monitoring instruments and dosemeters to be used in this environment. In the presented study, a suitable radiation field at PSI is investigated. The PSI High Intensity Proton Accelerator facility (HIPA) is a cascade of three accelerators that delivers a proton beam with a final energy of 590 MeV and at present a maximal current of 2.2 mA. The beam passes through two carbon targets used to produce secondary particles for experiments. These are heavily shielded by layers of concrete and iron. A collimation system ensures a reproducible position of the beam spot on the targets. This setup provides a steady neutron field with a dominant high-energy component outside the shielding above the targets. Considering normal operation of HIPA, this field is accessible from May to December with mean availability of 95%. In a first step, the neutron field was investigated using a survey instrument suitable for measurements of high-energy neutrons and an extended range Bonner Sphere spectrometer (ERBSS). The results are compared to Monte Carlo-simulations using the multi-purpose transport code FLUKA. The spectral neutron distribution obtained from the ERBSS measurements shows reasonable agreement with the spectral neutron distribution obtained from the simulations. In addition, the dose rate calculated from the spectrum and measured with the survey instrument agrees within the uncertainties. The results confirm that the investigated neutron field can be considered as a reference workplace field with a significant high-energy neutron component.

Presented author:
Alban Roussel - IRSN

Authors:
1.- ROUSSEL Alban, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), France 2.- L’HOMME Bruno, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), France 3.- TROMPIER François, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), France 4.- GRUEL Gaëtan, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), France 5.- DOS SANTOS Morgane, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), France

In most cases, radiological accidents lead to localized overexposures, resulting in the appearance of deterministic effects when a cutaneous dose of 2 Gy is exceeded. Better understanding of tissue reactions to different conditions is essential to improve the care of various radiological accident victims. Lesion gravity is proportional to the absorbed dose, but less information is available about the influence of X-ray beam quality on burn severity, which is the aim of this study. Localized paw expositions of C57Bl6/j mice were performed at 30 Gy (Kair) at 50 kV, 80 kV, 220 kV, 10 MV. Thanks to a complete dosimetric study by Monte Carlo simulations and experimental EPR measurements we can correlate the real absorbed dose to the biological effect. Lesion severity was quantified using a lesion score, transepidermal water loss (TWL) and cutaneous blood perfusion measurements. Radiopathological characterizations of muscle and bone were performed using microCT and histological analyses at various timepoints (up to 6 months post-irradiation). Low-energy X-ray led to less severe burns: lesion score shows a peak at D21 for low-energy X-ray, and less intense lesions from D14 to D21 for high-energy. TWL and cutaneous blood perfusion significantly increased at the lesion peak, with less intensity observed for the 10 MV group. Histological analyses highlighted a strong impact on the tibia growth plate (disorganization of chondrocyte cells, modification of proliferative zone). MicroCT analysis of bone are underway but significative decrease of the muscle volume at the lesional peak for low-energy X-ray with a trend to regeneration at 6 months was observed. This preclinical model highlighted the impact of the X-ray quality on lesion severity. To further understand the induced damage, additional histological analyses are in progress with the quantification of the extracellular matrix of muscle and specific staining of bone formation and resorption to characterize bone damage.

Presented author:
Matteo Ferrari - Laboratoire Hubert Curien, Université Jean Monnet Saint-Etienne

Authors:
M.Ferrari(1), Y.Q.Aguiar(1,2), A.Morana(1), A.Raj Mandal(1), L.Weninger(1), J.Perrot(1), R.García Alía(2), A.Alessi(3), O.Cavani(3), E. Novak(4), T.Peltan(4), A.Colangeli(5), S.Girard(1,6) 1. Université Jean Monnet Saint-Etienne, CNRS, Institut d'Optique Graduate School, Laboratoire Hubert Curien UMR 5516, F-42023, SAINT-ETIENNE, France. 2. Organisation Européenne pour la Recherche Nucléaire (CERN), CH-1211 Geneva 23, Switzerland. 3. LSI, CEA/DRF/IRAMIS, CNRS Ecole Polytechnique, Institut Polytechnique de Paris 91120 Palaiseau, France. 4. Centrum Výzkumu Řež s.r.o., Husinec- Rez, Czech Republic. 5. ENEA Department of Fusion and Technologies for Nuclear Safety and Security, Via Enrico Fermi 45, I-00044 Frascati (Roma), Italy. 6. Institut Universitaire de France (IUF), Ministère de l’Enseignement Supérieur et de la Recherche, Paris, France.

High level dosimetry is becoming pivotal for applications in intense radiation environments, such as particle accelerators, high-power targets, irradiation facilities, fission and fusion reactors, medical physics facilities, radioactive waste plants and space missions, where doses up to MGy levels are delivered by complex mixed radiation fields. Dosimetry techniques covering this range are extremely limited. CERN developed a readout system to extend the sensitivity of commercial FD-7 glass Radiophotoluminescent (RPL) dosimeters, normally used for occupational and personal dosimetry, up to MGy levels. RPL light, traditionally used for dose determination, is combined with transmission. Calibration is performed using 60-Co gamma radiation, however dosimeters are deployed along CERN’s accelerators where mixed fields are present. To verify the response dependency on various parameters at high doses, RPLs are being further characterized using radiation qualities such as X-rays at Laboratoire Hubert Curien (LabHC) up to MGy, 2.5 MeV electron irradiation up to 100 MGy at the SIRIUS platform of Laboratoire des Solides Irradiés, 14 MeV neutrons up to a fluence of 2.2 ×10^13 cm-2 in ENEA’s Frascati Neutron Generator, and up to 2.8× 10^13 cm-2 in a mixed neutron/gamma field at the LR-0 research reactor core from the Czech Republic Research Centre Řež, at doses up to 150 Gy(SiO2). We will present RPL signal and multi-wavelength transmission data in visible and near-infrared as measured at CERN and at LabHC after exposure to the mentioned irradiation conditions. Monte Carlo codes, such as PHITS are used to simulate the neutron and gamma dose components absorbed by the FD-7 material. The collected results deepen the understanding of FD-7 response in different irradiation conditions, for use in intense mixed radiation environments where other dosimeters might be difficult to implement. Advancements in the high-dose characterization for a refinement of the dosimetry techniques will be discussed, paving the way for application extensions.

Presented author:
Marija Majer - Ruđer Bošković Institute

Authors:
1. - Marija Majer - Ruđer Bošković Institute, Croatia 2. - Iva Ambrožová - Nuclear Physics Institute, Czech Republic 3. - Željka Knežević - Ruđer Bošković Institute, Croatia 4. - Michal Sadel - Institute of Nuclear Physics, Poland 5. - Cornelius Bauer - Heidelberg Ion Beam Therapy Center, Germany 6. - Mercedes Horvat - Ruđer Bošković Institute, Croatia 7. - Christina Mooshammer - German Cancer Research Center and Heidelberg University, Germany 8. - Christina Stengl - German Cancer Research Center and Heidelberg University, Germany 9. - Pawel Olko - Institute of Nuclear Physics, Poland 10. - Liliana Stolarczyk - Danish Centre for Particle Therapy, Denmark 11. - José Vedelago - German Cancer Research Center and Heidelberg University Hospital, Germany

The out-of-field doses may increase secondary cancer risk for radiotherapy patients. Particularly vulnerable group of patients are children. The aim of this study, carried out within EURADOS Working Group 9 (Radiation Dosimetry in Radiotherapy), is to evaluate and compare out-of-field doses in proton and light ion beam therapy for potential paediatric clinical scenarios. Measurements were carried out at the Heidelberg Ion Beam Therapy Center (HIT) using 1H, 4He, 12C and 16O ion beams. Radiobiological effectiveness (RBE)-optimised treatment plans for a virtual brain tumour in an anthropomorphic phantom representing a 10-year-old child were computed. Several types of dosimeters were placed in the organs of interest: two types of thermoluminescent detectors (MCP-7 and MCP-6) each having different sensitivity to neutrons, radiophotoluminescent detectors type GD-352M having very low sensitivity to neutrons and poly-allyl-diglycol-carbonate (PADC) nuclear track detectors which are detecting neutrons and ions but not sensitive to photons. Results obtained with MCP-7 and GD-352 (‘non-neutron doses’) are in good agreement. Observed differences might be caused by different sensitivity to neutrons and ions. The highest non-neutron dose, measured at thyroid, is about 40 microGy/Gy(RBE) for 4He and decreases over 25 microGy/Gy(RBE) for 1H and 12 microGy/Gy(RBE) for 12C to about 5 microGy/Gy(RBE) for 16O. The differences between MCP-6 and MCP-7 results, commonly regarded as indicators of thermal neutron dose, were several times less than MCP-7 results. The values measured by selected PADC detectors are in the range of several tens of microSv/Gy(RBE). To the best of authors’ knowledge, this is the first study aimed at comparing out-of-field doses in a paediatric patient phantom when irradiating the target with four different primary ions.

Presented author:
Satoshi Kodaira - National Institutes for Quantum Science and Technology

Authors:
1. Satoshi Kodaira, National Institutes for Quantum Science and Technology, Japan 2. Tamon Kusumoto, National Institutes for Quantum Science and Technology, Japan 3. Taisei Mamiya, National Institutes for Quantum Science and Technology, Japan 4. Teruaki Konishi, National Institutes for Quantum Science and Technology, Japan 5. Ryo Ogawara, RIKEN Nishina Center for Accelerator-Based Science, Japan 6. Nagaaki Kamiguchi, Sumitomo Heavy Industries, Ltd., Japan 7. Daizo Amano, Sumitomo Heavy Industries, Ltd., Japan 8. Kenzo Sasai, Sumitomo Heavy Industries, Ltd., Japan

Ultra-high dose rate radiation therapy, commonly known as FLASH, operates at dose rates over 40 Gy/s, which is 1,000 times higher than conventional radiation therapy (approximately 0.03 Gy/s). This method has garnered significant attention due to its potential to reduce side effects on normal tissue while maintaining therapeutic effectiveness. However, the underlying mechanisms of FLASH therapy remain unclear. It is hypothesized that the sparing effect of FLASH may be linked to the yield of water radiolysis products, which contribute to the radiation’s indirect action in causing DNA damage. To experimentally investigate the effects of ultra-high dose rate irradiation, we examined the dose-rate dependence of the yields of radiation-induced decomposition products in water. To support such research, it is crucial to validate dose measurements when the dose rate varies significantly. Additionally, the differences in detector response due to dose rate definitions such as average dose rate, pencil-beam scanning dose rate, and pulsed dose rate should be verified. In this study, we evaluated dose-rate dependences in various types of passive dosimeters, including optically stimulated luminescence dosimeters, Fricke chemical dosimeters, and cellulose triacetate film dosimeters, using 12 MeV electron pulsed beams and 230 MeV proton scanning beams. An extremely high pulsed dose rate of MGy/s, generated by short electron pulses with a width of 2 µs, induced significant saturation. These results provide valuable insights into acceptable dose and dose rate ranges for FLASH dosimetry.

Presented author:
Sarah Johanne Gade Clausen - Department of Physics and Astronomy, Aarhus University

Authors:
1. - Sarah J. G. Clausen, Department of Physics and Astronomy, Aarhus University, Aarhus, Denmark; Danish Centre for Particle Therapy, Aarhus University Hospital, Aarhus, Denmark 2. - Mads L. Jensen, Department of Physics and Astronomy, Aarhus University, Aarhus, Denmark 3. - Camilla L. Nielsen, Department of Physics and Astronomy, Aarhus University, Aarhus, Denmark 4. - Maria F. Jensen, Danish Centre for Particle Therapy, Aarhus University Hospital, Aarhus, Denmark 5. - Ludvig Muren, Danish Centre for Particle Therapy, Aarhus University Hospital, Aarhus, Denmark; Department of Clinical Medicine, Aarhus University, Aarhus, Denmark 6. - Christian S. Søndergaard, Danish Centre for Particle Therapy, Aarhus University Hospital, Aarhus, Denmark 7. - Peter S. Skyt, Danish Centre for Particle Therapy, Aarhus University Hospital, Aarhus, Denmark 8. - Line B. Stick, Danish Centre for Particle Therapy, Aarhus University Hospital, Aarhus, Denmark 9. - Esben Yates, Department of Medical Physics, Aarhus University Hospital, Aarhus, Denmark 10. - Simon H. Vindbæk, Danish Centre for Particle Therapy, Aarhus University Hospital, Aarhus, Denmark; Department of Clinical Medicine, Aarhus University, Aarhus, Denmark 11. - Peter Balling, Department of Physics and Astronomy, Aarhus University, Aarhus, Denmark

In radio therapy, accurate dose verifications are essential for ensuring patient safety, and particularly air-tissue interfaces, like the skin and internal cavities, can lead to considerable uncertainties in dose calculations. Patient-specific dose verification is typically conducted using a 2D ionization-chamber array for measuring specific treatment plans, but such dosimeters are typically limited in spatial resolution. This study explores the potential of a nanoparticle-based 2D optically stimulated luminescence (OSL) film dosimeter as an alternative for proton therapy dose verification. The (100x100x1.6mm3) OSL film consisted of chemically synthesized LiBaF₃ and LiF:Cu nanoparticles embedded in a transparent silicone elastomer, making the dosimeter flexible and suitable for conforming to complex surfaces. The OSL signal was stimulated using blue LED illumination and imaged onto a CCD-camera with a spatial resolution on the film of 1.16x1.16mm2. The dosimeter was irradiated with varying mono-energetic proton fields in the range ~80-200MeV, to assess its energy dependence. To investigate its dosimetric accuracy and resolution, the dosimeter was irradiated with a clinical proton-treatment field. Readings were compared to those from a conventional 2D ionization-chamber array, showing good agreement across the investigated energy range. Notably, the OSL film achieved a high dose-response sensitivity with a pixelwise noise-to-signal ratio remaining below 2% for doses above 1Gy, thus providing higher spatial resolution dose mappings than the ionization-chamber array. Despite limitations, such as higher noise than the chamber array at maximum spatial resolution, the OSL dosimeter exhibited linear dose response and negligible energy dependence in the tested ranges. Its flexibility also suggests potential use in 2.5D dosimetric applications, like surface dose measurements for irregular surfaces. Further studies will examine angular response and enhance adaptability for in-vivo measurements. In conclusion, the OSL dosimeter shows promise for high-resolution, reusable dosimetric verifications in both proton and photon therapies, advancing quality assurance in radio therapy.

Presented author:
Regina DeWitt - East Carolina University

Authors:
1. Regina DeWitt - Department of Physics, East Carolina University, Greenville, NC 27858, USA 2. A.R. Simms - Department of Earth Science, University of California Santa Barbara, Santa Barbara, CA, USA 3. K.M. Swanger - Environmental, Earth and Atmospheric Sciences, University of Massachusetts, Lowell, MA 01854, USA

Antarctica is the coldest, driest and windiest place on Earth and 98% of the continent are covered in ice. Despite the forbidding environment and dearth of accessible material, approximately 30 years ago the first luminescence dating studies were carried out with samples collected from the continent. Apart from attempts to date meteorites, the vast majority of studies has focused on climate change and its past and present impact on the Antarctic continent. This presentation will give an overview of various luminescence dating projects that have been carried out with Antarctic deposits. The main focus of the presentation will be on two geographic areas: the Antarctic Peninsula and the McMurdo Dry Valleys. Challenges inherent to Antarctic material will be discussed, including the approach of using rocks versus sediments. The Antarctic ice sheet holds approximately 61% of all fresh water on Earth, equivalent to about 58 meters of possible sea level rise. Sites along the Antarctic Peninsula have been used to quantify and predict the possible effect of current climate change, by investigating the connection between past climate change, melting of the Antarctic ice sheet, and sea level rise. GPS data from the last 20 decades reveal that the Antarctic continent is rising faster due to an increased rate of ice loss and the resulting isostatic adjustment. To determine how these uplift rates compare to rates from the last ~5,000 years, ages and elevations of ancient beaches on the Antarctic Peninsula have been determined. The Optically Stimulated Luminescence (OSL) ages of buried cobble-undersides reflect the last time the cobbles were turned over in the swash zone and thus the time elapsed since continental uplift raised the beach to an elevated level. The McMurdo Dry Valleys are the largest region on the Antarctic continent that is not currently glaciated by the ice sheets. However, the Dry Valleys do contain significant ice in the form of glaciers, buried glacial ice, and interstitial ice in near-surface sediments. Luminescence dating of meltwater lake deposits and deltas from meltwater streams has been used to investigate past climate change and dynamics of the ice sheet. This research has been funded through several grants from the National Science Foundation – Office of Polar Programs, including #1341284, #1643868, # 2039419.

Presented author:
Regina DeWitt - East Carolina University

Authors:
1. Regina DeWitt - Department of Physics, East Carolina University, Greenville, NC 27858, USA 2. A.R. Simms - Department of Earth Science, University of California Santa Barbara, Santa Barbara, CA, USA 3. K.M. Swanger - Environmental, Earth and Atmospheric Sciences, University of Massachusetts, Lowell, MA 01854, USA

Presented author:
DEBABRATA BANERJEE - Physical Research Laboratory

Authors:
D. Banerjee, Physical Research Laboratory, Ahmedabad, India D. R. Mishra, Bhabha Atomic Research Centre, Trombay, Mumbai, India D. K. Panda, Physical Research Laboratory, Ahmedabad, India Sanjeev N Menon, Bhabha Atomic Research Centre, Trombay, Mumbai, India Ajai Chikara, Bhabha Atomic Research Centre, Trombay, Mumbai, India Prashant Kr. Sharma, Bhabha Atomic Research Centre, Trombay, Mumbai, India

Mars' climate has shifted significantly over the past million years, as its axial tilt and orbit vary, and also because atmospheric pressure has changed with time. These changes and their effect on the Martian climate system are presently understood using GCMs. Since GCMs cannot be validated due to lack absolute ages on Mars, the timing of climate-related geological events is very poorly known. To this end, luminescence dating can unravel unresolved questions like timing, duration, and wind patterns driving aeolian modification of the Martian surface, and other features as sedimentary deposits transported in water, and glaciation events, previously unexplored in-situ by any of ongoing missions. Extensive hydrous sulfate layers have been associated with weathered Deccan Trap basalts in the Matanumadh area of Kachchh district, Gujarat state, western India. Based on the prevalence of the hydrous calcium-bearing sulfate mineral (minamiite) in sandstone beds overlying the weathered basalts at Matanumadh, it has been suggested that this area may be considered as a possible Martian analogue locality in India. X-ray diffraction patterns, along with hyperspectral reflectance spectral data in the visible near-infrared (350–2500 nm) to mid infrared (4000–400 cm-1) region and have been previously acquired on samples from Matanumadh for characterizing hydrous sulfates and phyllosilicate phases. In this study, we report the results of various experiments performed to characterize the optical and the infrared stimulated luminescence signals from several simulant samples from Matanumadh using a portable luminescence reader to test its suitability for determining luminescence ages of the Martian surface in a future lander/rover mission. The feasibility of the single-aliquot regeneration (SAR) protocol for equivalent dose estimation has been investigated and the implications regarding the upper age limit for optical dating of Martian sediments will be discussed. Elemental composition and mineralogical abundance measurements will be presented for the simulant samples.

Presented author:
Hiroshi Yasuda - Hiroshima University

Authors:
1. - Hiroshi Yasuda, Hiroshima University, Japan 2. - Ryuto Inobe, Hiroshima University, Japan 3. - Sophia Welti, Hiroshima University, Japan 4. -Yuka Yanagida, Chiyoda Technol Corporation, Japan 5. - Yasuhiro Koguchi, Chiyoda Technol Corporation, Japan

Workers and medical personnel who use high-intensity radiation sources on a daily basis are at risk of accidentally exposing their fingers to high levels of radiation, which could cause acute effects such as skin damage. For the prompt detection of such unexpected severe exposure, we attempted to use the radiochromic reaction of RPL glass that can be worn on the fingers to assess high-dose exposure using a simple scanning system. A plate-shaped RPL glass (FD-7) with the size of 8.0 × 8.0 × 1.5 mm3 used in a commercially available ring-type glass dosimeter (Glass Ring, Chiyoda Technol Co., Ltd.) was irradiated with 20 to 400 Gy of X-rays (160 kV, 6.3 mA). Radiation-induced coloration was visually confirmed on an LED tracing board (LED Tracer EX A4 Type-C Model No. E-7083, Etsumi Co., Ltd.), and the RGB images captured by an overhead scanner (Aura, CZUR Tech Co., Ltd.) (OHS) were analyzed using an image processing software (ImageJ). In addition, time changes in the post-irradiation absorbance spectra were measured using a UV-visible photospectrometer (V-560, JEOL Ltd.). The brownish color of the FD-7 glasses irradiated with ≥20 Gy X-rays, for which RPL measurements were difficult, was observed with the naked eye on the LED tracing board. From the analysis of the inverted images acquired by the OHS, the color intensity of blue component showed a nearly linear response to the dose. Interestingly, the blue color intensity became stable immediately after X-ray irradiation. The data obtained with the photospectrometer confirmed that the increase in absorbance over the RPL build-up period occurred only in the UV region (250-400 nm). This finding indicates that the monitoring method presented in this study has a practical advantage in that the preheating procedure, which is generally required in RPL glass dosimetry, can be omitted.

Presented author:
Michael Discher - University of Salzburg

Authors:
Michael Discher, Paris-Lodron-University of Salzburg, Department of Environment and Biodiversity, Salzburg, Austria Hyoungtaek Kim, Korea Atomic Energy Research Institute, Radiation Safety Management Division, Yuseong, Daejeon, Republic of Korea Céline Bassinet, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), F-92260, Fontenay-aux-Roses, France

Luminescence dosimetry is an important tool in retrospective dosimetry, facilitating the assessment of the absorbed dose subsequent to a radiological overexposure. Several components found in mobile phones and other electronic devices could serve as useful proxies for measuring the dose received by an individual. Various research groups have extensive experience in characterizing different elements for physical retrospective dosimetry, including electronic components, such as surface-mounted devices (SMD), display or touch screen glass, and so forth. In recent years, several measurement protocols have been developed for these components and tested in laboratory irradiations and field tests using the thermoluminescence (TL) or optically stimulated luminescence (OSL) methods. In this preliminary study, the TL using a red filter (RTL) was employed to reconstruct a X-ray dose provided by a LINAC (6 MV) utilising SMDs extracted from the circuit board of a smartwatch. The potential of the RTL method was demonstrated by TL emission spectra measurements (Lee et al., 2017) and a project report (Mafodda et al., 2019) using SMD components from a kit or mobile phone. The higher signal sensitivity of RTL indicated a reduction in the amount of material, which resulted in a faster sample preparation time, the potential for repairing a device, and a higher chance of dose reconstruction even with smaller components. The results of the dose recovery test showed a good agreement with the given dose; however, further systematic investigation is necessary to explain the observed dose overestimation. Generally, the RTL method could serve as an additional tool for retrospective dosimetry if the signal sensitivity is a crucial factor. References: Lee, J. et al., 2017. Thermoluminescence of chip inductors and resistors in new generation mobile phones for retrospective accident dosimetry. Radiat. Meas. 105, 26-32. Mafodda, A., Woda, C., Eakins, J., 2019. Deliverable 9.10 - Paper on external dosimetry using personal objects.

Presented author:
Stefan Schmidt - University Hospital Heidelberg (UKHD)

Authors:
1. Stefan Schmidt: Department of Radiation Oncology, Heidelberg University Hospital (UKHD), Heidelberg, Germany; Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany; Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany; Medical Faculty, Heidelberg University, Heidelberg, Germany; Heidelberg Ion-Beam Therapy Center (HIT), Department of Radiation Oncology, Heidelberg University Hospital (UKHD), Heidelberg, Germany. 2. Jeppe B. Christensen: Department of Radiation Safety and Security, Paul Scherrer Institute (PSI), Villigen PSI, Switzerland. 3. Benjamin Lutz: Physikalisch-Technische Bundesanstalt (PTB), Braunschweig, Germany. 4. Alberto Stabilini: Department of Radiation Safety and Security, Paul Scherrer Institute (PSI), Villigen PSI, Switzerland. 5. Eduardo G. Yukihara: Department of Radiation Safety and Security, Paul Scherrer Institute (PSI), Villigen PSI, Switzerland. 6. José Vedelago: Department of Radiation Oncology, Heidelberg University Hospital (UKHD), Heidelberg, Germany; Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany; Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany

In the context of ion beam radiotherapy, treatment fields are inevitably contaminated with secondary neutrons, some reaching energies of several hundred MeV. Fluorescent Nuclear Track Detectors (FNTDs) offer a promising option for neutron dosimetry, given their low linear energy transfer (LET) detection threshold. This study evaluates the sensitivity of FNTDs to fast mono-energetic and high-energy neutrons and explores the detector signal as a function of neutron energy. Ambient dose equivalent, H*(10), measurements were conducted by analyzing track density in microscope images and Monte Carlo (MC) simulations were employed to assess energy calibration factors and track parameters. For neutron fields up to 19 MeV, both neutron energy and converter thickness influenced the sensitivity: variation up to 22-fold with energy for FNTDs, while for poly allyl diglycol carbonate (PADC) detectors, it remained below a 12-fold variation. The converter thickness revealed a minor impact of about 1.5-fold. However, for high-energy neutrons up to 200 MeV, sensitivity varied by as much as a factor of 5 with different converter thicknesses. Therefore, utilizing MC-derived calibration factors, H*(10) values for different neutron fields were determined with deviations of less than 25 % compared to the reference dose. Simulations also provided insights into the recoil particle types and LET values recorded by FNTDs, revealing that recoil protons are the primary contributors to detector signal, while tritons, 4He, and deuterons account for about 15 % of the tracks at 150 MeV. The low average LET in water of about 6 keV µm-1 for recoil protons produced by high-energy neutrons represents an additional challenge in track detection. The findings of this study highlight the potential of FNTDs for accurate dosimetry of fast and high-energy neutrons in ion beam radiotherapy, enhancing out-of-field neutron dose assessment.

	ABC auditorium - Facultad de Ciencias, UNAM	Carlos Graef auditorium - Facultad de Ciencias, UNAM
08:30 - 09:00	Registration	Registration
09:00 - 09:30	Invited Talk 6 Linh Tran - Centre for Medical Radiation Physics, University of Wollongong "SOI Microdosimetry and its application in particle therapy"
09:30 - 10:30	Dosimetry for Medicine & Biology II - Moderators: Michael Hajek & Sarah Johanne Gade Clausen
09:30 - 09:45	Jeppe Brage Christensen - Paul Scherrer Institute (PSI) "First simultaneous dose, LET, and RBE measurements with OSL for helium ion beam therapy "
09:45 - 10:00	Olivier Van Hoey - SCK CEN "Combining passive detector measurements for out-of-field proton therapy dosimetry"
10:00 - 10:15	Jacob Johansen - Aarhus University Hospital "Inorganic-scintillator based dosimetry for an MR-Linac"
10:15 - 10:30	Tomas Kron - Peter MacCallum Cancer Centre "Carbon loaded TLDs: Utility in radiotherapy"
10:30 - 12:00	Poster session and coffee break at the Amoxcalli Lobby - Facultad de Ciencias, UNAM	Poster session and coffee break at the Amoxcalli Lobby - Facultad de Ciencias, UNAM
12:00 - 13:30	Dosimetry for Medicine & Biology III Moderators: Željka Knezevic & Tomas Kron	Monitoring and detection II Moderators: Patrícia Nicolucci & Wei-Sin Chen
12:00 - 12:15	Morgane Dos Santos - IRSN "Experimental and numerical dose characterization of an in vivo micro scanner to optimize preclinical longitudinal studies"	Eike Hohmann - Paul Scherrer Institute "First investigations of a new reference workplace field with a high-energy neutron component at PSI"
12:15 - 12:30	Alban Roussel - IRSN "Characterization of bone and muscle damage induced by different X-ray beam qualities and correlation to the real absorbed dose using a mouse model"	Matteo Ferrari - Laboratoire Hubert Curien, Université Jean Monnet Saint-Etienne "High-dose irradiation of FD-7 radiophotoluminescent glass dosimeters using mixed neutron and gamma radiation fields for extreme applications"
12:30 - 12:45	Marija Majer - Ruđer Bošković Institute "Out-of-field doses from ion beam radiotherapy of the paediatric brain tumour"	Balwan Hooda - Brookhaven National Laboratory "Comparison of the Performance of TLD, OSL and RPL Personal Dosimetry Systems to the American National Standard Institute (ANSI) Test Categories"
12:45 - 13:00	José T. Álvarez Romero - SSDL, Ionizing Radiation Metrology Department, ININ "Heuristic estimation of geometry correction factor k_sg for 137Cs LDR sources in the determination of the reference Kerma rate K ̇_R"	Roberto Bedogni - INFN-LNF "The evolution of Bonner Spheres into single moderator neutron spectrometers"
13:00 - 13:15	Satoshi Kodaira - National Institutes for Quantum Science and Technology "Characteristics of passive dosimeters for ultra-high dose rate electrons and protons"	Sergii Sholom - Brookhaven National Laboratory "Fading study of Harshaw LiF:Mg,Ti TL dosimeters exposed to neutron doses"
13:15 - 13:30	Sarah Johanne Gade Clausen - Department of Physics and Astronomy, Aarhus University "Reusable optically stimulated luminescence dosimetry films for 2D dose verification of proton therapy"	Yvone Mascarenhas - Sapra Landauer Serviço de Asse e Prot. Radiológica "Situation of Personal Dosimetry in Latin America and the Caribbean"
13:30 - 15:00	Lunch at the Physics Institute garden	Lunch at the Physics Institute garden
15:00 - 15:30	Invited Talk 7 Regina DeWitt - East Carolina University "30 Years of Luminescence Dating of Antarctic Deposits"	Invited Talk 7 (via zoom) Regina DeWitt - East Carolina University "30 Years of Luminescence Dating of Antarctic Deposits"
15:30 - 17:00	Dose Reconstruction and Dating II Moderators: Devesh R. Mishra & Alicja Chruścińska	Sponsor Session 2 Moderators: Yasuhiro Koguchi & Anna Cimmino
15:30 - 15:45	DEBABRATA BANERJEE - Physical Research Laboratory "Optically and infrared stimulated luminescence characterization of samples from Matanumadh, a Martian analogue site in Kachch, western India"	ROTUNDA Joe Rotunda - Rotunda Scientific Technologies "Dosimetry Low Dose to High Dose from Personal to Archaeological Dosimetry"
15:45 - 16:00	Hiroshi Yasuda - Hiroshima University "Monitoring of high-dose extremity exposure using radiochromic reaction of a ring-type RPL glass dosimeter"	Dosimetry Services - Mirion Medical Company Kip Bennett - Mirion Dosimetry "Mirion Dosimetry – Taking the Next Giant Leap in Personal Dosimetry"
16:00 - 16:15	Vladislava Fokina - Federal Office for Radiation Protection (BfS) "The potential of low-cost portable electronic devices for emergency dosimetry"	RadPro Ralf Hobein - RadPro International GmbH "Comprehensive OSL and TLD Solutions for the Personal Dosimetry"
16:15 - 16:30	Michael Discher - University of Salzburg "Preliminary results of SMD resistors using the red thermoluminescence method"	dosilab Miha Furlan - Dosilab "Dosilab technology for passive and active dosimetry"
16:30 - 16:45	Stefan Schmidt - University Hospital Heidelberg (UKHD) "Evaluating dosimetry performance of Fluorescent Nuclear Track Detectors in fast and high-energy neutron fields"
16:45 - 17:00	James Cayley - University of Wollongong "MOSkin dosimetry for ultra-high dose-rate, very high-energy electron radiotherapy"
17:00 - 18:30	Poster session and coffee break at the Amoxcalli Lobby - Facultad de Ciencias, UNAM	Poster session and coffee break at the Amoxcalli Lobby - Facultad de Ciencias, UNAM
20:00 - 00:00	Gala Dinner	Gala Dinner

Presented author:
Vinícius Souza Gomes - Universidade Federal de Sergipe

Authors:
Vinicius Souza Gomes, Departamento de Física, Universidade Federal de Sergipe, São Cristóvão, SE, Brazil Magno Nogueira Xavier, Departamento de Física, Universidade Federal de Sergipe, São Cristóvão, SE, Brazil Erison Fonseca Santos, Departamento de Física, Universidade Federal de Sergipe, São Cristóvão, SE, Brazil José Joatan Rodrigues Jr., Departamento de Física, Universidade Federal de Sergipe, São Cristóvão, SE, Brazil Francesca Barco, Scuola di Ingegneria, Università di Pisa, Pisa, Italy Francesco d'Errico, Scuola di Ingegneria, Università di Pisa, Pisa, Italy Susana de Souza Lalic, Departamento de Física, Universidade Federal de Sergipe, São Cristóvão, SE, Brazil

Photobiomodulation (PBM) has been shown to influence cellular behavior and is currently used as an adjunct in oncology to mitigate radiodermatitis and modulate tumor growth. Depending on specific parameters, PBM can either stimulate or inhibit cancer cell activity. However, the lack of standardized protocols and optimal parameters underscores the need for further research to establish clinically effective treatments. While in vitro studies provide insights, the difficulty of in vivo research continues to hinder protocol standardization. The plant model Allium cepa has proven effective as a biomarker for assessing radiation-induced damage, with endpoints such as micronuclei and chromosomal aberrations correlating with dose progression. This study aimed to evaluate the efficacy of PBM in reducing cytogenetic damage. Meristems of Allium cepa, previously irradiated with beta radiation, were exposed to red LED light (630 nm) at an early stage of radiation-induced damage. Controls included non-irradiated and irradiated samples without LED exposure. Results revealed a significant reduction in chromosomal aberrations and a marked increase in the mitotic index in irradiated cells treated with LED light. These findings suggest that red LED light can stimulate apoptosis in damaged cells while promoting the proliferation of healthy cells through mitosis. Furthermore, the observed non-proliferation and possible restoration of radioinduced cells provides valuable insights for radiogenetics, with potential applications in biotechnology. This study highlights the promising role of PBM in mitigating ionizing radiation damage, warranting further investigation to refine and standardize protocols for broader clinical application.

Presented author:
Min Chae Kim - Korea Atomic Energy Research Institute

Authors:
1.-Min Chae Kim, Korea Atomic Energy Research Institute, Republic of Korea 2.-Heagin Han, National Cancer Institute, United States of America 3.-Hyoungtaek Kim, Korea Atomic Energy Research Institute, Republic of Korea 4.-Sora Kim, Korea Atomic Energy Research Institute, Republic of Korea 5.-Yoomi Choi, Korea Atomic Energy Research Institute, Republic of Korea 6.-Jungil Lee, Korea Atomic Energy Research Institute, Republic of Korea 7.-Byung Il Min, Korea Atomic Energy Research Institute, Republic of Korea 8.-Chan Hyeong Kim, Hanyang University, Republic of Korea

Since the publication of the International Commission on Radiological Protection’s (ICRP) mesh-type reference computational phantoms (MRCPs), their applications across various radiation protection fields have grown significantly. Compared to voxel-based phantoms, MRCPs provide enhanced flexibility, making them particularly advantageous in scenarios that require adjustments to body shape and posture. Recent studies have assessed the dosimetric effects of 19 different postures using MRCPs, emphasizing the necessity of posture modifications in inhomogeneous radiation fields, such as those encountered during radiation accidents. Lead protective clothing is widely used to reduce radiation exposure across several sectors, including medical applications such as X-ray imaging, CT scans, and radiation therapy; industrial processes like non-destructive testing; operations, maintenance, and decommissioning activities in the nuclear industry; and research fields utilizing radiation. While some studies have integrated lead protective clothing into anthropomorphic computational phantoms, these efforts have primarily been limited to standing postures. Besides, modifying the body shape and posture requires redesigning protective clothing. In the present study, we designed lead shielding clothing by adding an extra layer atop the skin surface of a mesh-type phantom. This layer ensures compatibility with posture modifiable phantom because it is defined along the curves of the skin's surface. The clothing design was based on the structure of commercially available lead aprons used in nuclear power plant operations, a 3 mm for the front and a 1.5 mm for the back, with cuts positioned around the neck, above the buttocks, and along the groin area. The anthropomorphic phantom utilized in this study is a mesh-type model representing the standard body shape of Korean adults. Dose assessments were performed using the Geant4 code to evaluate the shielding effectiveness of the clothing on whole-body and organ doses across various exposure scenarios, including AP, PA, LLAT, RLAT, ROT, ISO, etc. orientations.

Presented author:
Francesca Barco - Università di Pisa

Authors:
1.- Francesco d'Errico, School of Engineering, University of Pisa, Pisa, Italy. 2.- Corresponding Authors: Francesca Barco, School of Engineering, University of Pisa, Pisa, Italy. 3.- Tommaso Butini, Department of Biological, Chemical, and Pharmaceutical Sciences and Technologies “STEBICEF”, University of Palermo, Palermo, Italy. 4.- Mariagrazia Quattrocchi, Department of Radiology, St. Luca Hospital, Lucca, Italy. 5.- Riccardo Ciolini, School of Engineering, University of Pisa, Pisa, Italy. 6.- Susana de Souza Lalic, Departamento de Física, Universidade Federal de Sergipe, São Cristóvão-SE, Brazil. 7.- Maurizio Marrale, Department of Physics and Chemistry “Emilio Segrè”, University of Palermo, Palermo, Italy. 8.- Andrea Malizia, Department of Biomedicine and Prevention, University of Roma 2, Tor Vergata, Italy. 9.- Fabio Caradonna, Department of Biological, Chemical, and Pharmaceutical Sciences and Technologies “STEBICEF”, University of Palermo, Palermo, Italy.

The escalating threat of radiological and nuclear accidents or attacks has underscored the urgent need for effective radioprotective measures. In this context, our ongoing research focuses on the development and testing of non-toxic, dietary supplements of natural origin. Unlike traditional animal-based models, our innovative approach employs a vegetable-based test model, specifically the meristems (root tips) of Allium cepa (onion). This model offers a rapid, cost-effective, and ethically acceptable alternative for evaluating radioprotective compounds. Our research aims to identify and characterize radioprotective compounds that can safeguard both military personnel and civilians against radiation exposure. The radioprotectors to be evaluated include extracts of grape-vines (Vitis vinifera) and prickly-pear cactus (Opuntia), which have shown promising antioxidant and anti-inflammatory properties. These extracts will be assessed for their ability to mitigate radiation-induced damage in the onion meristems. Preliminary results indicate promising radioprotective effects in select compounds, which warrant further investigation. Our research has significant implications for the development of effective countermeasures against radiation exposure, aligning with global efforts to enhance nuclear security and mitigate the consequences of radiological incidents.

Presented author:
Vincent de Rover - University of Wollongong

Authors:
1. Vincent de Rover, Centre for Medical Radiation Physics (CMRP), University of Wollongong, Australia 2. Jason Paino, Centre for Medical Radiation Physics (CMRP), University of Wollongong, Australia 3. Angela Kok, SINTEF Digital, Department of Microsystems and Nanotechnology, Norway 4. Marco Petasecca, Centre for Medical Radiation Physics (CMRP), University of Wollongong, Australia 5. Marco Povoli, SINTEF Digital, Department of Microsystems and Nanotechnology, Norway 6. Linh T. Tran, Centre for Medical Radiation Physics (CMRP), University of Wollongong, Australia 7. Matthew Large, Centre for Medical Radiation Physics (CMRP), University of Wollongong, Australia 8. Elette Engels, Centre for Medical Radiation Physics (CMRP), University of Wollongong, Australia 9. Matthew Cameron, Australian Synchrotron, Imaging and Medical Beamline, Australia 10. Anatoly Rosenfeld, Centre for Medical Radiation Physics (CMRP), University of Wollongong, Australia 11. Michael Lerch, Centre for Medical Radiation Physics (CMRP), University of Wollongong, Australia

This investigation focusses on the response of an epitaxial Schottky Silicon Carbide (SiC) detector, when exposed to intense synchrotron x-ray radiation. For a detector to be used for dosimetry in these type of radiation fields, the detector ideally should have a response similar to that of human tissue, and be able to withstand high dose rate environments. When investigating the response of the SiC detector at different beam energies, some energy dependence of the detector is observed. There is also some indication of irradiation dose rate dependence. Lower (pink) beam energies at the Australian Synchrotron, for a given wiggler field strength leads to higher irradiation dose rates (range is from ~120Gy/s to ~7000Gy/s). However, excellent dose linearity is observed, for the SiC detector for all the doses investigated (up to 2300 Gy), when measured at a dose rate of 120Gy/s. Extended dose linearity experiments revealed some radiation damage in the SiC detector. We observed a decrease in the photogenerated current of 17% after a total irradiation dose of 150,000 Gy. The corresponding ideality factor and barrier height was also determined a few days before and after delivery of 150,000 Gy. The ideality factor was calculated to be 2.04 ± 0.13 and 1.96 ± 0.05 respectively, and barrier height calculated to be (1.144 ± 0.033) V before exposure and (1.146 ± 0.016) V after exposure, indicating these parameters aren’t dependent on the dose delivered. The average integral region of the detector when exposed to the 4T, Cu-Cu (additional pink beam filtration) synchrotron x-ray field environment, had increased by a factor of 1.78 ± 0.14 after being exposed to 150,000 Gy, along with greater uncertainty in the integral region after 150,000 Gy exposure. Although initially the detector responded well to intense synchrotron radiation fields, its response worsened when exposed to large doses.

Presented author:
Ryosuke Narita - Grad. Sch. Engr, Kyoto Univ.

Authors:
1.-Ryosuke Narita, Grad. Sch. Engr., Kyoto Univ., Japan 2.-Masao Gohdo, Saitama Univ., Japan 3.-Shin-ichiro Hayashi, Hiroshima International Univ., Japan 4.-Yoshinori Sakurai, Institute for Integrated Radiation and Nuclear Science, Kyoto Univ., Japan

For verification of quality assurance (QA) in boron neutron capture therapy (BNCT), the following three are important: 1. High-resolution, wide-range, real-time, and easier dose estimation method, 2. Dose component discrimination method, and 3. Flexible shape of dosimeter. Gel dosimeters are expected to meet these requirements, and we especially focus on radiochromic gel dosimeters with leucocrystal violet (LCV). A feasibility study was performed for the dose estimation method using LCV dosimeters. Preliminary experiments were performed using the Co-60 gamma-ray irradiation facilities mainly at Institute of Scientific and Industrial Research, Osaka University. In these experiments, the following three were confirmed: 1. Sampling and analysis of RGB color data, 2. Obtaining spatial distribution using layered dosimeters, 3. Obtaining time variation by video recording. The linearity of the dose response was most consistent with the gray scale (Y=0.587G+0.229R+0.114B), but the dose response was slightly decreased immediately after the irradiation due to the response with the red scale. Otherwise, the green scale was selected for the analysis of spatial and temporal dose distributions because of its better sensitivity and linearity in response to the green scale. The dose distribution using layered gel dosimeters was verified for spatial off-axis distribution at the 1st layer gel dosimeter with simulation. The time variation was constant of 1.03 Gy/min at the 1st layer gel dosimeter which was almost same as the theoretical water-equivalent dose rate. Pilot experiment for neutron irradiation is now on performed using Heavy Water Neutron Irradiation Facility of Kyoto University Research Reactor. From the results of the preliminary and the pilot experiments, the feasibility of the dose distribution estimation method using gel dosimeters for QA in BNCT was confirmed. It was also identified that some improvements were needed in the sensitivity of gel dosimeters, the imaging system, etc..

Presented author:
Antonella Mele - Department of Radiation Safety and Security, Paul Scherrer Institute

Authors:
Antonella Mele a,b , Jeppe Brage Christensen a , Mathieu Hursin b , Eduardo G. Yukihara a

Neutron dosimetry plays a crucial role in ensuring radiation protection across multiple domains, including nuclear power generation, medical diagnostics and therapy, and high-energy physics experiments. Nevertheless, obtaining precise neutron dose measurements remains difficult due to the wide energy range of neutrons - spanning more than ten orders of magnitude - which influences both the reaction types and the corresponding cross-sections. Similarly, the fluence-to-dose conversion coefficients can fluctuate by up to an order of magnitude depending on neutron energy. This work is dedicated to developing a predictive model for PADC detectors and the entire dosimetry procedure, which includes exposure, etching, read-out, and dose estimation. The goal is to systematically address each step of the process, accounting for all factors that could potentially affect the accuracy of neutron dosimetry. By integrating a Monte Carlo simulation of the detector's irradiation conditions with a semiempirical model for track formation and evolution, and by developing new algorithms for track recognition that overcome the limitations of current commercial read-out systems, we seek to predict the detector's efficiency for any neutron spectrum and irradiation geometry. The model is currently under development and will be validated under standard conditions through both simulations and experimental measurements using well-characterized neutron sources such as ²⁴¹AmBe and ²⁵²Cf. Future work will aim to extend the model's applicability to a wider range of neutron energies and incident angles, with additional testing in realistic workplace neutron fields. Our objective is to enhance the energy response and efficiency of one of the most commonly used personal neutron dosimeters while enabling predictive modeling of its response in complex or insufficiently characterized neutron fields. This capability is especially crucial in settings like nuclear reactors or high-energy accelerators, where neutron spectra can significantly differ from calibration conditions, thereby increasing measurement uncertainty and inaccuracy.

Presented author:
DEBABRATA BANERJEE - Physical Research Laboratory

Authors:
R.P. Bourman, University of Wollongong, Australia Debabrata Banerjee, Physical Research Laboratory, India Dipak K Panda, Physical Research Laboratory, India C. V. Murray-Wallace, University of Wollongong, Australia W. Preiss, Geological Survey of South Australia S. Buckman, University of Wollongong, Australia

Optically stimulated dating of Ngankipari Formation, southern South Australia. R. P. Bourman , Debabrata Banerjee, D. K. Panda, C. V. Murray-Wallace, W. Preiss and S. Buckman We have performed Optically stimulated luminescence (OSL) dating at Ngankipari Formation, a weakly consolidated calcareous and silty sand occurring in a succession of Quaternary terrestrial sediments in the Noarlunga Embayment of the Cenozoic St Vincent Basin, South Australia. An early Holocene age was suggested by Ward (1966) for this unit, based on its inferred association with an Aboriginal midden with molluscs, which returned Holocene radiocarbon ages. Bourman et al. (2022) tentatively assigned the Ngankipari Sand to the Last Glacial Maximum (MIS 2). OSL ages are determined using the single-aliquot regenerative-dose procedure, are used to infer two informal members at two separate sites; a younger dated at 262±26 ka and 253±31 ka and an older dated at 381±27 ka. These new OSL ages are significantly older than the early Holocene and late Pleistocene ages previously suggested for the Ngankipari Formation. The ages of the two members correlate with sea levels lower than at present, Marine Isotope Stage 8 and the retreating sea level phase in late MIS 11, respectively. These were glacial and interstadial phases when the continental shelf was subaerially exposed, thereby supplying a source for wind-borne sediments to the terrestrial realm. Bourman, R.P., Barnett, S.R., Murray-Wallace, C.V. & Buckman, S., Debabrata Banerjee and Dipak Panda (2022). A stratigraphic revision of the Pleistocene succession in the Noarlunga and Willunga Embayments, South Australia. MESA Journal, 96: 27– 36 Ward W.T. (1966). Geology, geomorphology, and soils of the south-western part of County Adelaide, South Australia, Soil Publication 23. CSIRO.

Presented author:
Kassym Zhumadilov - L.N. Gumilyov Eurasian National University

Authors:
Zhumadilov K.S.1, Ivannikov A.I.2, Khailov A.M.2, Stepanenko V.F.2, Kazymbet P.K.3, Bagramova A.A.1, Kassymzhanov M.T.1, Nasilov Z.O.1, Toyoda S.4, Hoshi M.5 1L.N. Gumilyov Eurasian National University, Munaitpasova 13, Astana 010008, Kazakhstan 2A.F. Tsyb Medical Radiological Research Center, 4, Korolev str., Obninsk, 249036, Russia 3Astana Medical University, Astana, Kazakhstan 4Department of Applied Physics Faculty of Science Okayama University of Science, 700-0005, Japan 5Hiroshima University, 734-8553, Japan Presenting Author: zhumadilovk@gmail.com

Tooth enamel samples from staff of the uranium mining enterprise in comparison with the population of the control territory have been investigated by the EPR dosimetry method. The extraction of uranium often leads to a significant accumulation of radioactive materials in the environment. To assess the radiation impact of uranium mining enterprises on the personnel of enterprises and the population of the adjacent territories, the personnel of the Shantobe uranium mine and the population of Stepnogorsk (Akmola region, Northern Kazakhstan) were examined by the EPR dosimetry method. On the basis of the measurements performed, a statistical analysis of the obtained values of the added doses obtained by the EPR method of dosimetry for tooth enamel separately for population groups and personnel was carried out. For the population of Stepnogorsk (50 teeth samples) the average dose was 4 +/- 11 mGy, of 51 mGy. For the personnel of the Shantobe uranium mining enterprise (30 teeth samples) the average dose value is 95 +/- 20 mGy, a variation of 85 mGy. For some samples of personnel, an assessment of the possible contribution of AI by comparing RS in samples before and after etching of the surface layer was carried out. A higher average dose value and a larger variation for personnel are probably due to the contribution of occupational exposure. Probably, part of this contribution is due to internal irradiation from alpha sources in the soft tissues of the body. This work was supported by the Ministry of Education and Science of Kazakhstan (This research has been/was/is funded by the Science Committee of the Ministry of Science and Higher Education of the Republic of Kazakhstan (Grant № AP19678341). Keywords: EPR dosimetry, Stepnogorsk, teeth sample. Shantobe. References 1. IAEA, 2002. IAEA-TECDOC-1331, Vienna: International Atomic Energy Agency; 2002.

Presented author:
Jae Seok Kim - Korea Institute of Radiological and Medical Sciences

Authors:
1. Jae Seok Kim, Korea Institute of Radiological and Medical Sciences, Republic of Korea 2. Byeong Ryong Park, Korea Institute of Radiological and Medical Sciences, Republic of Korea 3. Byungmin Lee, Korea Institute of Radiological and Medical Sciences, Republic of Korea 4. Han Sung Kim, Korea Institute of Radiological and Medical Sciences, Republic of Korea 5. Seokwon Yoon, Korea Institute of Radiological and Medical Sciences, Republic of Korea 6. Ki Hoon Kim, Korea Institute of Radiological and Medical Sciences, Republic of Korea 7. In Mo Eo, Korea Institute of Radiological and Medical Sciences, Republic of Korea 8. MinSeok Park, Korea Institute of Radiological and Medical Sciences, Republic of Korea 9. Minsu Cho, Korea Institute of Radiological and Medical Sciences, Republic of Korea

Monte Carlo method using a computational phantom has the advantage to accurately evaluate the radiation protection quantity by simulating the radiation exposure situation including the posture of individuals. In the case of complex exposure condition, the dose reconstruction method based on a physical human phantom and dosimeters can be applied to assess the radiation dose. Through this approach, dose reconstruction method combined Monte Carlo method and physical dose assessment method can be used in complementary manner to evaluate the radiation protection quantity. In this research, the irradiation experiment was conducted to verify the physical dose assessment method based the physical human phantom and radiophotoluminescent glass dosimeters (RPLGDs). The initial model of physical human phantoms were produced by dividing the whole body phantom of adult male (176 cm in height, 73 kg in weight) and adult female (163 cm in height, 60 kg in weight) into slices. Three types of materials were used for the physical human phantoms, and the materials were made of equivalent materials that could represent soft tissue, bones, and lungs. The results of organ doses and effective dose evaluated by RPLGDs inserted in the physical human phantoms were compared by Monte Carlo simulation method in the same condition as the irradiation experiment. The relative bias of effective dose evaluated by measurement and Monte Carlo simulation obtained using 60Co and 192Ir sources was evaluated as 6.45% and -21.95% respectively. The results revealed that the effectiveness of the physical dose assessment method in the specific energy of gamma rays, and factors that could cause experimental errors which identified by comparing with Monte Carlo simulation. The physical dose assessment method completed through additional verification experiments will be applied to evaluate a radiation epdemiology study for Korean worker study.

Presented author:
Faycal Kharfi - Setif1 University-Ferhat Abbas

Authors:
1.-Faycal Kharfi, Setif1 University-Ferhat Abbas, Algeria 2.-Eren Şahiner, Earth Sciences Application and Research Centre of Ankara University, Turkey 3.-Chadia Khalafallah, National Public Museum of Setif, Algeria 4.-Mahfoud Bououdene, National Public Museum of Setif, Algeria 5.-Layachi Boukerdja, Nuclear Research Centre of Birine, Algeria

Despite its long history, Algerian Islamic pottery and ceramics have not been widely studied, and much of the knowledge about this important aspect of Algeria's cultural heritage remains fragmented. Nevertheless, it continues to be an important part of Algeria's cultural identity and serves as a testament to the country's rich artistic heritage. This Algerian Islamic pottery refers to ceramics produced in Algeria during the Islamic period, typically between the 8th and 19th centuries. In this work, ceramics fragments from bowls, plates, and jars are studied. Samples are collected around Hammadite Islamic historical cities and castles of M’sila and Bejaia localities. Six ceramics fragments fabricated with double firing technique were dated using thermoluminescence (TL) method. Moreover, the origins of the used material for their fabrication were identified through a statistical comparison of their compositions to a reference dataset of row materials. The considered samples and materials were analyzed using X-ray fluorescence technique (XRF). Results of TL dating show that most of the dated fragments are from the 10th and 12th centuries, period of time that is corresponding to the Hammadite regency between M’sila and Bejaia. The errors on age reach in some cases reach 25%. Comparisons between row materials and ceramics fragments compositions allow us to conclude that the studied ceramics fragments are locally fabricated except for one fragment (sample N°3) where no hard evidence and no correlation with the considered row materials dataset were found. Indeed, for most ceramics fragments, the performed statistical test demonstrate well that the used manufacturing materials fit well with the row materials collected from deposits around the Hammadite cities and castles such as Oued Fredj in M’sila.

Presented author:
Daniela Constantin - , Interdisciplinary Research Institute on Bio-Nano-Sciences, Babeș-Bolyai University

Authors:
1. Daniela Constantin, Interdisciplinary Research Institute on Bio-Nano-Sciences, Babeș-Bolyai University, Romania 2. Aditi K. Dave, Interdisciplinary Research Institute on Bio-Nano-Sciences, Babeș-Bolyai University, Romania 3. Șerban Grecu, Interdisciplinary Research Institute on Bio-Nano-Sciences, Babeș-Bolyai University, Romania 4. Zuzanna Kabacińska, Interdisciplinary Research Institute on Bio-Nano-Sciences, Babeș-Bolyai University, Romania and Geochronology Research Unit, Institute of Geology, Faculty of Geographical and Geological Sciences, Adam Mickiewicz University, Poland 5. Andris Antuzevics, Institute of Solid State Physics, University of Latvia, Latvia 6. Anca Barla, Department of Geosciences, University of Arizona, Arizona, USA 7. Petru Urdea, Department of Geography, West University of Timișoara, Romania 8. Mihai N. Ducea, Department of Geosciences, University of Arizona, Arizona, USA and Faculty of Geology and Geophysics, University of Bucharest, Romania 9. Alida Timar-Gabor, Interdisciplinary Research Institute on Bio-Nano-Sciences, Babeș-Bolyai University, Romania and Faculty of Environmental Science and Engineering, Babeș-Bolyai University, Romania

Quartz optically stimulated luminescence (OSL) sensitivity as well as some electron spin resonance (ESR) and cathodoluminescence (CL) signals have been empirically proposed as provenance indicators. OSL sensitivity is defined as luminescence emitted in response to a given dose per unit mass. While it is largely believed to be acquired by earth surface processes, recent studies bring evidence that sensitisation processes depend on source geology. Here we combine OSL and thermoluminescence (TL), ESR and CL analyses to understand the mechanisms of quartz OSL sensitisation. We investigate granites and their derived sediments from catchments draining simple lithologies of known age that display contrasting OSL sensitisation behaviour both in nature and during irradiation and light exposure laboratory experiments. The sample displaying increased OSL sensitisation is characterised by TL emission at intermediate temperatures (150-250 °C), Ti-related signals in CL, and Ti and Ge lithium compensated signals in ESR. The insensitive samples either lack or exhibit very weak such characteristics and contain several times less amount of trace titanium measured by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). We demonstrate that the OSL sensitisation results as an effect of the existence of certain defects and impurities in the quartz crystal in the parent rock, such as titanium and germanium. However, the degree of sensitisation reached in nature is significantly higher than in the laboratory. As such, the existence of this precursor represents the potential for sensitisation, which can later be amplified by environmental factors during sedimentary history.

Presented author:
Kazuki Takegami - Yamaguchi University Hospital

Authors:
1.-Tatsuya Maeda, Kanazawa University, Japan 2.-Sota Goto, Kobe Tokiwa University, Japan 3.-Takashi Asahara, Okayama University, Japan 4.-Natsumi Kimoto, Junshin Gakuen University, Japan 5.-Rina Nishigami, Kanazawa University, Japan 6.-Daiki Kobayashi, Kanazawa University, Japan 7.-Hiroaki Hayashi, Kanazawa University, Japan

Medical diagnosis using computed tomography (CT) images is widely performed in many situations, and therefore radiation exposures for patients should be managed. However, direct measurement with small-type dosimeters is challenging during the helical CT scan because radiation exposure varies with the incident direction of the X-rays. This study aims to gain new insight into internal dose measurements from entrance surface doses (ESD) that take into consideration the X-ray incident direction. Cylindrical polyacetal resin (POM) phantoms having diameters of 15–30 cm were prepared. The phantoms have a hole in the center in which a rod embedding a small OSL dosimeter can be inserted. The ESD and the internal dose were measured with dosimeters placed on the surface and center of the phantom, respectively. The X-ray incident direction of the slice in which the dosimeters were placed was analyzed from the image noise distribution of CT images. The correction related to the X-ray incident direction was performed by making the relationship between the incident direction and the ESD. Furthermore, the relationship between the internal dose and the corrected ESD was also derived. When correcting the effect of the X-ray incident directions, the deviation of the ESDs was reduced to be 15% although it was 50% without the correction. For the internal dose, the deviation was at most 8% which does not depend on the X-ray incident direction. In the correcting procedure, the ratios of the internal dose to the ESD using the cylindrical phantoms with different diameters of 15, 20, 25, and 30 cm were determined as 1.16, 1.00, 0.83, and 0.63, respectively. We concluded that correcting the effect of the X-ray incident directions can provide novel experimental knowledge for evaluating the internal dose.

Presented author:
Nancy Kuniko Umisedo - Universidade de Sao Paulo

Authors:
1. Isaias Petronis, isaias.petronis@hc.fm.usp.br, Brazil 2. Denise Yanikian Nersissian, yanikian@if.usp.br, Brazil 3. Francisco Shibayama Cancio, fcancio@if.usp.br, Brazil 4. Nancy Kuniko Umisedo, numisedo@if.usp.br, Brazil 5. Elisabeth Mateus Yoshimura, yoshimura@usp.br, Brazil

Interventional radiology procedures are the primary source of radiation exposure for healthcare workers, making personal dosimetry essential for ensuring their protection. This study aimed to estimate the average radiation dose to the team involved in the most common interventional procedures at the Instituto de Radiologia, Hospital das Clínicas, Universidade de São Paulo (USP). Personal dose equivalent Hp(10) outside the lead apron was assessed with the techniques and equipment of a certified laboratory (Instituto de Física da USP) using thermoluminescent dosimetry (TL). The ambient dose equivalent H*(10) at the arc of the Innova 4100 IQ angiography system (GE®️) was also determined in clinical procedures, with the same techniques Under controlled equipment settings simulating clinical procedures, TL readings were compared with measurements obtained from an ionization chamber (IC) and the equipment's dose indicator. 57 percutaneous transhepatic biliary drainage procedures were monitored, and doses to the five types of professionals that usually participate in the procedure were obtained: three interventional radiologists, one anesthesiologist and one circulating nurse. For each procedure different staff members performed each one of the five roles, but the same dosimeter badge was used for various procedures and the results were interpreted as average values for this kind of examination and staff role. Results from controlled irradiations showed a strong linear relationship between TL and IC measurements (R² = 0.979). TL results and the equipment’s dose indicator values demonstrated linear correlations in both clinical procedures and controlled evaluations. The average Hp(10) per procedure for the main interventionalist, who was positioned closest to the irradiated region, was 0.321 ± 0.067 mSv during drain replacement and 0.54 ± 0.10 mSv during drain insertion procedures. TL readings for the anesthesiologist and circulating nurse were below the detection threshold due to their positioning in relation to the patient.

Presented author:
Takashi Asahara - Okayama University

Authors:
1. Takashi Asahara, Okayama University, Japan 2. Tatsuya Maeda, Kanazawa University, Japan 3. Rina Nishigami, Kanazawa University, Japan 4. Daiki Kobayashi, Kanazawa University, Japan 5. Sota Goto, Kobe Tokiwa University, Japan 6. Natsumi Kimoto, Junshin Gakuen University, Japan 7. Kazuki Takegami, Yamaguchi University Hospital, Japan 8. Mitsugi Honda, Okayama University Hospital, Japan 9. Toshihiro Iguchi, Okayama University, Japan 10. Hiroaki Hayashi, Kanazawa University, Japan

During medical examinations using an X-ray fluoroscopy system, operators such as medical doctors standing near the patient are exposed to scattered X-rays. Generally, their radiation doses are monitored by personal dosimeters, but these dosimeters cannot analyze the angle of the X-rays. In this study, we propose a wearable active-type dosimeter that has the ability to analyze the incident direction and absolute dose of X-rays. If the incident angle could be analyzed, not only the angular dependence of the dosimeter can be corrected, but also valuable information for radiation protection will be obtained. Our dosimeter system consists of three active-type dosimeters. The central dosimeter is the commercial dosimeter (RaySafe i3, Unfors RaySafe, Sweden), which is used to derive the absolute dose rate in which angular dependence is corrected by the proposed method. The side dosimeters (RaySafe i2, Unfors RaySafe) are used to determine the incident direction. These side dosimeters are symmetrically tilted 45 degrees outwards in the horizontal plane and are equipped with a symmetrical titanium sloped filter. Since the incident X-rays are attenuated differently in the slope filters of the two tilted dosimeters, we can analyze the incident angle. In order to validate the capabilities of our dosimeter, a basic experiment using a fluoroscopic system was carried out. Our dosimeter was able to analyze the incident angles between -75 and +75 degrees with an accuracy of 5 degrees. Furthermore, the absolute dose rate can be determined without the systematic uncertainty related to the angular dependence. Although the original dosimeter had a systematic uncertainty of 11.1% due to angular dependence, our system reduced this uncertainty to 3.2%. In conclusion, our dosimeter, combining three active-type dosimeters, worked correctly over a 150-degree range and allowed for accurate determination of absolute dose with the correction of the angular dependence.

Presented author:
Sota Goto - Kobe Tokiwa University

Authors:
1. Sota Goto, Kobe Tokiwa University, Japan 2. Takuya Kasue, Kobe Tokiwa University, Japan 3. Keiji Takahisa, Kobe Tokiwa University, Japan 4. Tatsuya Maeda, Kanazawa University, Japan 5. Kazuki Takegami, Yamaguchi University Hospital, Japan 6. Takashi Asahara, Okayama University, Japan 7. Natsumi Kimoto, Junshin Gakuen University, Japan 8. Hiroaki Hayashi, Kanazawa University, Japan

Computed tomography (CT) is performed to diagnose diseases, but its contribution to medical radiation exposure should be reduced. To manage medical exposure accurately, it is effective to measure the patient’s dose directly using a radiation dosimeter. During helical scanning CT, the exposure dose at the patient’s surface position varies depending on the X-ray source positions, making it difficult to measure the mean dose using a few passive dosimeters. In addition, many of the active-type dosimeters capable of real-time measurements are not suitable for patient dosimetry during CT examination because they lead to metal artifacts in the CT images. The purpose of this research is to develop a small active-type dosimeter that does not generate metal artifacts. Our dosimeter is made of the Optically Stimulated Luminescence (OSL) sheet and Multi Pixel Photon Counter (MPPC). Although OSL dosimeters have been usually used as passive-type dosimeters, real-time signals can be obtained by measuring the prompt emission of the stimulated luminescence. The size of our prototype dosimeter was 20 mm × 30 mm × 5 mm. Then, to demonstrate the applicability of the developed dosimeter, experiments using helical scanning were performed ten times in which the dosimeter was placed on the cylindrical water phantom. The effect of a metal artifact was evaluated from a standard deviation of the CT value with and without the dosimeter. A commercial semiconductor dosimeter was also used for comparison. Real-time signals due to direct X-rays and scattered X-rays were obtained at 0.1-second intervals. We plan to analyze these signals in more detail and develop an algorithm to estimate the positional information of the X-ray tube. In addition, we found that the artifact due to our dosimeter was less than half of the commercial semiconductor dosimeter. It is expected that our dosimeter can be applicable to actual patient dosimetry.

Presented author:
Wilmer Melo Bernal - Secretaria de Educación Distrital, Bogotá

Authors:
1. W. Melo-Bernal, Secretaria de Educación Distrital, Bogotá, Colombia 2. M. Barboza-Flores, Departamento de Investigación en Física, Universidad de Sonora, Mexico 3.V. Chernov, Departamento de Investigación en Física, Universidad de Sonora, Mexico

Proton therapy takes advantage of the Bragg peak to effectively target cancer cells while minimizing damage to surrounding healthy tissues, establishing itself as a leading-edge cancer treatment modality. However, the relatively low relative biological effectiveness (RBE) of protons compared to heavier ions can limit therapeutic outcomes. Incorporating radiosensitizers such as gold nanoparticles (GNPs) presents a promising approach to enhance RBE, thereby amplifying therapeutic impact within tumors. This study focuses on simulating the dose deposition in the vicinity of GNPs of various radii (r = 2, 10, 25, and 50 nm) under two conditions: irradiation with monoenergetic proton beams at therapeutic energies (2, 80, 100, and 300 MeV) and exposure to the mixed radiation field that reaches the treated volume. The simulations were performed using the Monte Carlo code TOPAS. The simulations followed a three-stage process: (1) irradiation of a water phantom (a 10 × 10 × 5 cm3 box of water equivalent tissue) to generate the mixed radiation field at the target depth, with phase space scoring; (2) interaction modeling of the mixed field with GNPs, scoring electrons emitted from the nanoparticles (using g4em-livermore physical models); and (3) dose deposition assessment in the GNP vicinity accounting for Auger cascades and primary ionization processes. To ensure sufficient statistical accuracy and reasonable computational time, the number of incident protons was fixed at 10^8. Our results reveal a significant increase in the range of secondary electrons that are produced by the projectile impact on the GNP as the energy of the incident protons increases. Notably, lower proton energies exhibited higher dose deposition near the GNPs, with nanoparticle size playing a critical role in modulating the dose enhancement. These findings suggest that optimizing GNP size and proton energy could maximize the therapeutic potential of proton therapy enhanced by high Z nanoparticles.

Presented author:
Hiroaki Hayashi - Kanazawa University

Authors:
1. Hiroaki Hayashi, Kanazawa University, Japan 2. Tatsuya Maeda, Kanazawa University, Japan 3. Kazuki Takegami, Yamaguchi University Hospital, Japan 4. Sota Goto, Kobe Tokiwa University, Japan 5. Rina Nisigami, Kanazawa University, Japan 6. Daiki Kobayashi, Kanazawa University, Japan 7. Takashi Asahara, Okayama University, Japan 8. Natsumi Kimoto, Junshin Gakuen University, Japan 9. Yuki Kanazawa, Tokushima University, Japan 10. Kazuta Yamashita, Tokushima University, Japan 11. Takeshi Konishi, Meditec Japan, Co., Ltd., Japan 12. Motochika Maki, Meditec Japan, Co., Ltd., Japan

Computed tomography (CT) examinations are the main cause of medical radiation exposure, and therefore the radiation dose should be optimized. However, it is challenging to measure patient data, because the position of the X-ray tube during a CT scan is randomly determined. It is necessary to evaluate the effect of the X-ray tube position on the dose measurement results. The purpose of this study is to develop a method to correct the difference in the position of the X-ray tube during CT examination. Clinical data were obtained from patients who underwent chest CT scans. A small OSL dosimeter was provided to each patient, and the radiation dose was measured at the center of the chest. The amount of X-ray exposures was automatically determined using the automatic exposure control (AEC) system. The incidence direction of the X-rays on the dosimeter’s slice was analyzed from the X-ray CT image. The analysis results were analyzed by plotting the data in which the horizontal and vertical axes show the X-ray incidence direction and the determined dose, respectively. This relationship is a function for correcting the effects of the X-ray tube position, and was clarified for the first time in this study. To take into consideration the influence of patient body size, we conducted case-specific categorization based on Body Mass Index (BMI). Compared with the data set of standard body size humans (2025) had a +9% dose increase. Three cases of very high radiation exposure were identified in the high BMI patient group, and it was concluded that they were due to patient-related factors and not to the position of the X-ray tube.

Presented author:
Eduardo López-Pineda - Universidad Nacional Autónoma de México

Authors:
Jorge Luis Lucho-Cervantes, Facultad de Ciencias, Universidad Nacional Autónoma de México 04510, Mexico City, Mexico Guerda Massillon-JL, Instituto de Física, Universidad Nacional Autónoma de México 04510, Mexico City, Mexico Eduardo López-Pineda, Instituto de Física, Universidad Nacional Autónoma de México 04510, Mexico City, Mexico

Radiochromic films are widely used in the clinic for measuring absorbed dose received by patients. However, before using them, their dosimetric characteristics should be evaluated. Some years ago, XR-QA2 Gafchromic film has been released into the market for a number and complex medical diagnostic procedures using low-energy X-rays. Recently, the new LD-V1 film model became commercially available as its successor. This work presents the dosimetric characteristic comparison between these two film models after exposure to 10 X-ray beam qualities ranging from 20 kV to 160 kV at air kerma values between 10 Gy and 200 Gy. We evaluated the energy as well as the dose-rate dependence. Film sheets were cut into pieces of 1.2×1.2 cm2 and for each air kerma value, three pieces were considered. The reading process was carried out in reflection mode in an Epson Expression 11000XL document scanner at 300 dpi and 48 bit- RGB color depths following the protocol previously established and only the red and green channels were analyzed. The film response was assessed considering the air kerma and the absorbed dose deposited into the film sensitive volumes. For the red channel, both films exhibited a higher response and lower uncertainty compared to the green. When considering the air kerma, the LD-V1 film response is less energy dependence than XR-QA2. While, if the dose within the film is considered an inverse behavior is observed. Both film models exhibit an over-response below 20 keV effective energy. It was concluded that both films are very similar, with no clear advantages or disadvantages. This project is partially supported by the European Commission Horizon MSCA- SE Project MAMBA (Grant No.101131245) and PAPIIT-UNAM (Grant No. IN106825 and IN103025)

Presented author:
Samayeh Azariasl - Hiroshima University

Authors:
1. Samayeh Azariasl,Research Institute for Radiation Biology and Medicine (RIRBM),Hiroshima University,Japan 2. Hiroshi Yasuda, Research Institute for Radiation Biology and Medicine (RIRBM),Hiroshima University,Japan 3. HIDEAKI FUJITA,Research Institute for Radiation Biology and Medicine (RIRBM),Hiroshima University,Japan 4. Tomonobu Watanab,Research Institute for Radiation Biology and Medicine (RIRBM),Hiroshima University,Japan

The increasing use of radiation sources across various fields has heightened the risk of radiological accidents. The ESR/EPR spectroscopy using accessible tissue materials such as fingernails offers potential for retrospective dose assessment. However, practical methods for accurately assessing individual radiation doses remain challenging due to the complexity and inter-individual variability in ESR signals. This study aimed to develop an individual-based protocol for fingernail ESR dosimetry by analyzing radiation sensitivity, age-related differences in ESR signals, and molecular structural changes using Raman spectroscopy to provide deeper insights on the mechanism of radical formation in fingernails. Samples of fingernails were collected from 15 donors (Asian type) of different ages and genders, and the aliquots of every individual with 160 kV X-rays were exposed to 0 and 20 Gy to simulate the emergency exposure. All irradiated fingernails were measured 1 hr after irradiation with an X-band ESR spectrometer (9.4 GHz). In addition, by using Raman spectroscopy in three different spots on nail samples, we observed changes in the amount of molecular bonds relating to sulfur of hard keratin and biomolecular variations in different age groups. According to ESR data, the signal intensities showed a significant difference among younger donors, especially children, exhibiting stronger signal responses to the 20 Gy dose compared to the control (0 Gy). In addition, significant Raman shifts and intensity differences were observed between the control and irradiated samples, and the ESR signals and amount of sulfide bonds demonstrated a significant correlation across different age groups. These results suggest that human fingernails, being readily accessible biological materials, hold potential as bioindicators for dose assessment during major radiological incidents, while they highlight the importance of conducting individual-based calibrations to enable the practical application of this fingernail ESR dosimetry method. Keywords: ESR/EPR spectroscopy;Fingernail dosimetry;Raman Spectroscopy;Radiation accident

Presented author:
Joel Beazley - University of Oxford

Authors:
1. Joel Beazley, University of Oxford, Oxfordshire 2. Arzhang Ardavan, University of Oxford, Oxfordshire 3. Jonathan Eakins, UK Health Security Agency, Chilton, Oxfordshire 4. Rick Tanner, UK Health Security Agency, Chilton, Oxfordshire 5. Robert Gougelet, Global Resonance Technologies, Shelburne, VT 6. Ian Speers, Global Resonance Technologies, Shelburne, VT

Alanine is often used in medical dosimetry, and allows dosimetric estimates by measuring the number of radicals produced through Electron Paramagnetic Resonance (EPR) spectroscopy. However, it could also potentially find application as an emergency dosemeter following a large-scale radiological incident, to provide dose estimates to patients in order to triage them, and support limited biodosimetric methods. The postulation of an alanine pellet embedded within identity cards (an ‘alanine card’) carried by the general public is one that would greatly improve emergency preparedness, provided a sufficient minimum detectable dose can be achieved. A deployable reader with sufficient sensitivity would be able to undertake a clinically relevant dosimetric reading of such a card immediately after an incident within the timescale of minutes. This study aims to demonstrate the feasibility of alanine-card-based emergency dosimetry. Novel electronic hardware that will allow an alanine card to be measured through EPR measurements was designed in a high frequency electromagnetic simulation software (Ansys HFSS), and will be built and tested on alanine cards irradiated with varying doses. Simulations suggest that the use of this resonator could improve on the sensitivity of the current transmission line method by a factor of ~1,000. Computational modelling was performed in MCNP using a voxel phantom to estimate the uncertainty in dose estimates from a worn alanine card, due to the attenuation of a person between the source and the pellet. By modelling an alanine pellet worn in various positions on the body, the relative change in dose received by a pellet as a function of source orientation around the phantom was simulated for various photon energies. Further simulations were done for isotropic and rotational sources. Together, these studies provide insight into the limits on the potential reliability of alanine cards for providing accurate dosimetry for individuals following a radiological incident.

Presented author:
Nancy Jovaana Zuñiga Rivera - UNISON

Authors:
1.- Nancy Jovaana Zuñiga-Rivera, Departamento de Investigación en Física, Universidad de Sonora, México. 2.- Rodrigo Melendrez-Amavizca, Departamento de Investigación en Física, Universidad de Sonora, México. 3.- Rodolfo Ruiz-Torres, Departamento de Investigación en Física, Universidad de Sonora, México. 4.- Pedro Salas-Castillo, Centro de Física Aplicada y Tecnología Avanzada, UNAM, México. 5.- Marcelino Barboza-Flores, Departamento de Investigación en Física, Universidad de Sonora, México.

Recently, materials that emit light in the red/near-infrared region have gained significant interest due to their potential applications in the biological field, particularly for tracking various targets in diagnostic imaging. In this study, we present the photoluminescence (PL) and thermoluminescence (TL) characteristics of MgGa1.99O4:0.01Cr3+, which was synthesized using the combustion method. The material was synthesized stoichiometrically from magnesium nitrate, gallium nitrate, and chromium nitrate in an aqueous solution. After thorough homogenization, urea was added as fuel while maintaining constant agitation. The mixture was then placed in a preheated oven at 550 °C until an exothermic reaction occurred. The resulting flakes were ground into a fine powder for further characterization. X-ray diffraction analysis revealed the presence of peaks associated with MgGa2O4 oxide (ICDD PDF 00-089-3082). The photoluminescence was measured using a Flurolog Horiba Jobin-Yvon Model FL-1039 spectrometer. The material exhibited major emission peaks at 328 nm, 414 nm, 436 nm, and 702 nm, with excitation wavelengths of 290 nm, 356 nm, 376 nm, and 420 nm, respectively. Thermoluminescence measurements were conducted using a Riso TL/OSL reader model DA-20, utilizing X-ray radiation with settings of 50 kV and 1 mA from a filament tube. The exposure times for the X-rays varied from 5 seconds to 36000 seconds (up to 10 hours), with intervals of 60 seconds at 20.0 kV and 0.25 mA. For all exposure times, a defined TL curve was observed, with intensity increasing as X-ray radiation increases, peaking at a maximum emission temperature of 167 °C.

Presented author:
María Vicela Hernández López - UASLP

Authors:
1.- María Vicela Hernández López, Universidad Autónoma de San Luis Potosí (UASLP), Mexico. 2.- Carlos Alejandro Moreno Aguilar, Universidad Autónoma de San Luis Potosí (UASLP), Mexico. 3.- Héctor Gerardo Barrientos Luna, Centro Regional de Enfermedades Oncológicas (CREO), Mexico. 4.- Daniel de la Cruz Hernández, Instituto Nacional de Investigaciones Nucleares (ININ), Mexico. 5.- José Trinidad Álvarez Romero, Instituto Nacional de Investigaciones Nucleares (ININ), Mexico.

The AAPM-TG-138/GEC-ESTRO:2011 report establishes an expanded uncertainty of U(k=2)≤6.8% in Dw(x,y,z) for high-energy brachytherapy sources to achieve success in radiological patient safety and tumor volume control. Hence it is necessary to implement a suitable dose verification methodology for HDR 60Co sources. The dosimetric algorithm Rivard-et-al AAPM-TG-43U:2004 and Ballester-et-al AAPM-ESTRO-TG-43-2012 for the Dw(x,y,z) is implemented in an Excel spreadsheet employing the dosimetric functions reported by Ballester-2005 and the 60Co source E&Z-BEBIG series BB-AC868 with Sk=13.33mGy/h±2.6% at 20/09/2024 determined with the Standard-Imaging-HDR1000-Plus-A963391-Well-Chamber calibrated at the NPL for 192Ir; and the use of the quality factor, kQ=1.050±2.1%, for 60Co reported by Schuller-et-al-2015. Additionally, the Dw(2 cm,90°) is experimentally determined: a) with an Exradin-A19-thimble-chamber-series-XAQ091622 with traceability to the BIPM, b) with Isodose-Curves obtained by the radiochromic films: GAFCHROMIC-EBT-HD-810, processed with Matlab, c) and, with the verification of Dw(2 cm,90°) done for a nominal value of 2Gy with TLD-100. The value of Dw(2cm,90°)=36.04Gy/hr±7.6% was obtained with the manual application of the TG-43 functions and its uncertainty with the GUM. On the other hand, the TPS-SagiPlan reports for the rate Dw(2cm,90°)=36.33Gy/h±7.4%. The value obtained with the Farmer chamber is Dw(2cm,90°)=31.40Gy/h±10.3%, which was obtained from the ionization measurements corrected by kPT=1.25±0.24% and the Kondo factor, kKondo=1.34±10%, and a NDw=5.0E7Gy/C±1.5% for the A19-chamber. The value determined with the radiochromic film is 31.0Gy/h±35%. Finally, for the case of the TLD-100, a Dw value of 1.92Gy±3.3%, and 1.76Gy±3.2%, were obtained for a source length of 4 and 3 mm modeled with the TPS, respectively. Analysis of the results shows reasonable consistency between the experimental Dw values determined with the ionization chamber and the TPS, within 10%, except for the radiochromic film, which is characterized by limited precision. In the case of the TLD-100, it is evident that the source modeling with a length of 3 mm underestimates the Dw(2cm,90°).

Poster session at the Amoxcalli Lobby - Facultad de Ciencias, UNAM
Vinícius Souza Gomes - Universidade Federal de Sergipe Optimizing Photobiomodulation Parameters Using Plant Stem Cells YSA
Hassna Bantan - HU On-site radiochromic film dosimetry using smartphone cameras YSA
Min Chae Kim - Korea Atomic Energy Research Institute Design and evaluation of lead protective clothing compatible with a posture-modifiable computational anthropomorphic phantom YSA
Francesca Barco - Università di Pisa A Fully Plant-Based Approach to Mitigating Radiation Exposure YSA
Vincent de Rover - University of Wollongong SiC detector response to intense synchrotron x-ray radiation fields YSA
Ryosuke Narita - Grad. Sch. Engr, Kyoto Univ. Feasibility study for dose distribution estimation using gel dosimeters for quality assurance in boron neutron capture therapy YSA
Antonella Mele - Department of Radiation Safety and Security, Paul Scherrer Institute Advancing track-etched detectors for accurate neutron dosimetry
DEBABRATA BANERJEE - Physical Research Laboratory Optically stimulated dating of Ngankipari Formation, southern South Australia.
Kassym Zhumadilov - L.N. Gumilyov Eurasian National University Exposure doses estimation to uranium personnel of the mining enterprise and the population of Akmola region, Kazakhstan
Jae Seok Kim - Korea Institute of Radiological and Medical Sciences Verification of physical dose assessment method based the physical human phantom and RPLGDs for evaluating the radiation protection quantity
Kassym Zhumadilov - L.N. Gumilyov Eurasian National University Exposure doses estimation to uranium personnel of the mining enterprise and the population of Akmola region, Kazakhstan
Faycal Kharfi - Setif1 University-Ferhat Abbas Thermoluminescence dating and identification of the origins of the materials used for the fabrication of some Algerian Islamic potteries and ceramics
Daniela Constantin - , Interdisciplinary Research Institute on Bio-Nano-Sciences, Babeș-Bolyai University Tracing quartz provenance: a multi-disciplinary investigation of luminescence sensitisation mechanisms of quartz from granite source rocks and derived sediments
Shailesh Joshi - IGCAR Quantification of Quartz using FTIR from Materials of Dosimetric Interest
Kazuki Takegami - Yamaguchi University Hospital Technological development of the relationship measurement between surface and internal doses during helical CT examinations: a phantom study
Nancy Kuniko Umisedo - Universidade de Sao Paulo Radiation Exposure Assessment in Interventional Radiology: Staff Personal Dosimetry and Radiation Protection in Percutaneous Transhepatic Biliary Cholangiography
Takashi Asahara - Okayama University X-ray dose determination of medical staff during fluoroscopic examination: A novel wearable dosimeter system that can analyze incident direction of radiation
Sota Goto - Kobe Tokiwa University Development of active-type OSL dosimeter for measuring patient surface dose during CT examinations
Wilmer Melo Bernal - Secretaria de Educación Distrital, Bogotá Gold nanoparticles as radiosensitizers in monoenergetic MeV proton irradiation and mixed field scenarios: an in-silico study using TOPAS
Hiroaki Hayashi - Kanazawa University Impact of different X-ray tube positions on dose measurement results during CT examinations
Eduardo López-Pineda - Universidad Nacional Autónoma de México Dosimetric properties between Gafchromic films XR-QA2 versus LD-V1
Maria Karampiperi - Medical Radiation Physics, Dept. of Translational Medicine, Lund University IndAccDos: investigation of novel methods for INDividualised ACCident DOSimetry
Samayeh Azariasl - Hiroshima University Fingernail ESR Dosimetry:Investigation of Interindividual Sensitivity and Molecular Analysis
Joel Beazley - University of Oxford Testing the use of alanine-based chip cards for emergency personal dosimetry following ionising radiation exposures
Nancy Jovaana Zuñiga Rivera - UNISON PL and X-ray TL response of chromium-doped magnesium gallate synthesized by combustion method.
Aldo Jair Valdiviezo Sanchez - UAM In vivo dosimetry for total body irradiation using radiochromic film
María Vicela Hernández López - UASLP Verification of Physical Dosimetry of the Absorbed Dose Rate to Water D´w(x,y,z) for HDR 60Co BEBIG Model A.86 source
Amiel Gayol - UNC & CONICET Self-developed PENELOPE-Penhan-Based geometry manager for Monte Carlo dosimetry simulations in presence of magnetic fields: Comparisons with Elekta MR-LINAC Unity treatment planning system
Ellen Vilarinho da Silva - Rio de Janeiro State University Monte Carlo dose estimation and optimization in mammography
Beatriz Moreira Magiore - UNESP Calculation of Secondary Electron Energy Deposition Produced by Ions in PMMA

Friday June 13, 2025

Presented author:
Hyoungtaek Kim - Korea Atomic Energy Research Institute

Authors:
1.-Hyoungtaek Kim, Korea Atomic Energy Research Institute, Republic of Korea 2.-Hyungjoon Yu, Korea Institute of Nuclear Safety, Republic of Korea 3.-Ah Reum Kim, Korea Institute of Nuclear Safety, Republic of Korea 4.-Jeong Tae Lee, Korea Institute of Nuclear Safety, Republic of Korea 5.-Hanjin Lee, Korea Institute of Nuclear Safety, Republic of Korea 6.-Jongheon Kim, Korea Institute of Nuclear Safety, Republic of Korea 7.-Min Chae Kim, Korea Atomic Energy Research Institute, Republic of Korea 8.-Jungil Lee, Korea Atomic Energy Research Institute, Republic of Korea

Retrospective dosimetry encompasses a range of techniques used to estimate the radiation dose received by individuals from past exposures, such as radiological accidents, where conventional dosimetry methods were absent or insufficient. These techniques primarily focus on quantifying changes in the physical properties of materials induced by ionizing radiation. Key methods include biological dosimetry, which evaluates DNA damage in blood samples; electron paramagnetic resonance (EPR), which measures free radicals in bones or nails; and thermoluminescence/optically stimulated luminescence (TL/OSL), which detects luminescence emitted from trapped charges in specific materials. Among these, TL/OSL techniques stand out for their faster measurement times and lower detection limits, making them particularly well-suited for triage during the initial stages of large-scale radiation incidents. Promising materials for TL/OSL dosimetry include smart chip cards from credit or ID cards, surface-mounted resistors (SMR), display glasses, and IC chips from mobile phones. Additionally, other materials such as tobacco, salt, dental ceramics, drugs, and pharmaceuticals have been explored for their potential use in this field. While numerous cases of biological and EPR dosimetry have been reported in small-scale overexposure accidents, the application of luminescence dosimetry using personal belongings has yet to be documented. This study presents dose assessments conducted using TL/OSL techniques in actual radiation exposure accidents that occurred in South Korea from 2016 to 2024. These assessments were carried out through collaboration between the Korea Institute of Nuclear Safety (KINS) and the Korea Atomic Energy Research Institute (KAERI). KINS, a specialized agency responsible for nuclear and radiation safety regulation and evaluation, investigates radiation overexposure incidents exceeding the annual dose limit at workplaces. These investigations involve site inspections, interviews, and dose assessments, employing various retrospective dosimetry techniques as needed. TL/OSL methods were applied with the consent of the exposed individuals and business operators, focusing on personal items, such as mobile phones and electronic personal dosimeters, presumed to have been carried during the incident. The implemented protocols include TL and OSL of resistors and prebleached TL of display glasses. These protocols have been previously validated through intercomparison exercises and field experiments conducted within EURADOS WG10 and RENEB. Personal electronic devices were disassembled under a red light and the components such as SMRs and display glass layers were extracted and pretreated following recommended protocols. Luminescence signals were measured using a Risø DA-20 TL/OSL reader. For incidents with known exposure times, a single fading factor was applied; for those with unknown times, multiple fading factors were used to ensure conservative dose estimates. Reconstructed doses ranged from below the minimum detectable dose (MDD) to several Gy, depending on the case. This study introduces several real-world accident scenarios, compares TL/OSL dose assessments with other dosimetry methods, and discusses the considerations, potentials, and limitations of TL/OSL techniques in small-scale radiological accidents. Acknowledgments: The study was carried out under the National Research Foundation of Korea (NRF) grant funded by the Korean government (Ministry of Science and ICT) (RS-2022-00144350, RS-2022-00144210) and KAERI (Project number 521410-23).

Presented author:
Neilo Trindade - USP

Authors:
1.-Matheus C. S. Nunes, Universidade Estadual Paulista (UNESP), Brazil. 2.-Miguel L. Rodrigues, Serviço Nacional de Aprendizagem Industrial (SENAI), Brazil. 3.-Walace J. R. Silva, Universidade Estadual Paulista (UNESP), Brazil. 4.-Ronaldo S. Silva, Universidade Federal de Sergipe (UFS), Brazil. 5.-Nancy K. Umisedo, Instituto de Física - Universidade de São Paulo, Brazil. 6.-Elisabeth M. Yoshimura, Instituto de Física - Universidade de São Paulo, Brazil. 7.-Neilo M. Trindade∗, Instituto de Física - Universidade de São Paulo, Brazil.

Thermoluminescence (TL) and Radioluminescence (RL) are widely used in dosimetry applications. We present a custom-built integrated system, designated LUMI-22, for measuring TL, TL spectroscopic, RL, and RL as a function of temperature. LUMI-22 includes a heating system based on Kanthal® A1 alloy (FeCrAl), a microcontroller to regulate the temperature ramps (e.g. 1 – 5 ºC/s). To irradiate samples an X-ray tube (Moxtek 50 kV, 50 µA) is powered, controlled, and monitored by an FTC-200 standard controller. The dose rate at the sample position is 0.43 Gy/min. Light collection includes a Photomultiplier Tube (PMT, Hamamatsu H10493-012:HA, 185 to 850 nm). Additionally, a miniature fiber optic spectrometer (Ocean Optics, QE65000, range 200-1100 nm) coupled with a 1000 µm diameter fiber optic (QP1000- 2-UV-VIS) was employed for TL and RL spectroscopy measurements. To assess the functionality of the system, it was used to measure TL and RL from Al2O3:C,Mg, Al2O3:C and TLD-100 phosphors which have been previously well investigated. The measured TL and RL compared well with published ones, a confirmation of the functionality of the system. Efforts are currently underway to implement Optically Stimulated Luminescence (OSL), further expanding the system's applications in radiation detection. Acknowledgments: N. M. Trindade is grateful to FAPESP (#2018/05982–0; #2019/05915–3; #2024/03006-4) and CNPq (#409338/2021–4). W. J. R. Silva is grateful to FAPESP (#2021/00626- 3) and CAPES. M. C. S. Nunes is grateful to FAPESP (#2021/12758-1; #2022/14516-8; #2023/18315-0). R. S. Silva is grateful to FAPESP (#2021/08653-0). E. M. Yoshimura is grateful to FAPESP (#2018/05982–0) and CNPq (#311657/2021–4).

Presented author:
Yuriy Zorenko - Kazimierz Wielki University in Bydgoszcz

Authors:
V. Gorbenko1, T. Zorenko1, S. Witkiewicz-Łukaszek1, P. Bilski2, M. Gryziński3, B. Sobiech4, J. Winiecki4,5, Yu. Zorenko1,4* 1Department of Physics Kazimierz Wielki University in Bydgoszcz, Powstańców Wielkopolskich str., 2, 85-090 Bydgoszcz, Poland 2Institute of Nuclear Physics Polish Academy of Sciences, Radzikowskiego str. 152, PL31342 Krakow, Poland 3National Centre for Nuclear Research, A. Sołtana str. 7/3, 05-400 Otwock-Swierk, Poland 4Medical Physics Department, Prof. Franciszek Łukaszyk Oncology Center, I. Romanowska str., 2, 85-796 Bydgoszcz, Poland 5Department of Oncology and Brachytherapy, Collegium Medicum in Bydgoszcz of Nicholas Copernicus University in Torun, Jagiellonska str. 13/15, 85-067 Bydgoszcz, Poland corresponding author: zorenko@ukw.edu.pl

This work is devoted to the development of new concept for studying the effects of secondary radiation in boron neutron capture therapy based on the application of multilayer composite scintillation detectors. Such composite detectors can be used for simultaneous measurement of the dose of various types of ionizing radiation, including 7Li ions, α-particles and γ-rays. The principle of these composite detector working is based on the use of significantly different pathways of high-LET corpuscular particles (7Li, α), and low-LET quanta (γ-rays) in multilayer luminescent materials. For this purpose, different types of composite detectors based on the single crystalline films and single crystals of Y3Al5O12 and Lu3Al5O12 garnets, doped with Ce3+, Pr3+ and Sc3+ ions, were produced using the liquid phase epitaxy growth method and their luminescent and scintillation properties were investigated as well. The thickness of the top luminescent materials, based on the relatively “light” Y3Al5O12 garnet films, was selected close to the path of the 7Li and α-particles, when the lower part of detector was contain appropriately thick substrate of heavy Lu3Al5O12 garnet intended for recording high-energy γ-rays. The fiber-optic scintillation reader for in-situ dose measurement of different radiation components at BNCT was constructed based on the developed types of composite detectors, long optical fiber and sensitive luminescence spectrometer. The possibility of recording various radiation components was demonstrated using: 1) the differences in the pulse height spectra and scintillation decay kinetics of various parts of composite detectors under excitation by α-particles of 239Pu source; 2) the difference in the radioluminescence spectra of films and crystal scintillators in composite detectors under excitation by γ-rays of 192Ir (392 keV) source. The obtained results were discussed for choice of the best registration methods and types of composite detectors for direct dose measurements of secondary radiation under excitation 10B contaning materials with thermal neutrons.

Presented author:
Tristan Genetay - Lausanne University hospital (CHUV) / CERN

Authors:
1.-Tristan Genetay, Institute of Radiation Physics, Lausanne University Hospital (CHUV) and Lausanne University, Switzerland & CERN, Switzerland 2.-Lukas Tlustos, IEAP Institute for Experimental and Applied Physics, Czech Technical University in Prague, Czech Republic & CERN, Switzerland 3.-Michael Campbell, CERN, Switzerland 4.-François Bochud, Institute of Radiation Physics, Lausanne University Hospital (CHUV) and Lausanne University, Switzerland 5.-Pierre Carbonez, CERN, Switzerland & University of Otago, Christchurch, New Zealand 6.Jérôme Damet, Institute of Radiation Physics, Lausanne University Hospital (CHUV) and Lausanne University, Switzerland & University of Otago, Christchurch, New Zealand

The evolution of imaging equipment in radiology theatres, together with the increasing complexity of procedures and the lack of information provided by manufacturers on filtration, i.e. X-ray spectral characteristics, has made it increasingly difficult to accurately assess the actual exposure of hospital staff. Radiation protection equipment could be optimised by knowing the energy spectrum to which the user is exposed. The Timepix3 chip has already proved to be an efficient tool for generating maps of scattered radiation around X-ray imaging modalities in hospitals and paved the way for a broader use of this technique. The release of Timepix4 and its significant technical improvements widens the field of possibilities even further. The Timepix4 chip is the latest hybrid pixel detector readout ASIC in the Timepix family, developed at CERN. The detector has a matrix of 448 x 512 pixels and can record up to 360 Mhits/cm2/s. Its capacity to measure reference X-ray beam qualities in diagnostic radiology has been evaluated. This study presents energy spectra acquired for primary beams across several reference qualities within the RQR series, using a Timepix4 detector with a 300 µm-thick silicon sensor. The detector was tested with RQR7 (90 kVp) and RQR9 (120 kVp) beam qualities at varying currents (from 0.5 to 6 mA). The measured spectra were compared with Monte Carlo simulations and published reference spectra. All spectra measurements were corrected for silicon photon detection efficiency and pixel sharing. The results were then compared to Monte Carlo simulations to assess measurement accuracy. Spectra for RQR beams showed strong agreement with simulations for both beam qualities at 0.5 and 3 mA, while data at 6 mA indicated detector saturation, aligning with the bandwidth limits of the current readout system. These results highlight the potential of the Timepix4 chip for primary beam measurement applications in diagnostic radiology.

Presented author:
Vladimir Pan - UOW

Authors:
1. Vladimir A. Pan, Centre for Medical and Radiation Physics, University of Wollongong, Australia 2. Linh T. Tran, Centre for Medical and Radiation Physics, University of Wollongong, Australia 3. James Vohradsky, Centre for Medical and Radiation Physics, University of Wollongong, Australia 4. Enrico Pierobon, GSI Helmholtzzentrum für Schwerionenforschung, Germany 5. Luca Lunati, GSI Helmholtzzentrum für Schwerionenforschung, Germany 6. Tim Wagner, GSI Helmholtzzentrum für Schwerionenforschung, Germany 7. Adam L. Gera, GSI Helmholtzzentrum für Schwerionenforschung, Germany 8. Moritz Kasemann, Institute of Aerospace Medicine, German Aerospace Center, Germany 9. Daniel Matthiae, Institute of Aerospace Medicine, German Aerospace Center, Germany 10. Andreas Waets, CERN, Geneva, Switzerland 11. Natalia Emriskova, CERN, Geneva, Switzerland 12. Anatoly Rosenfeld, Centre for Medical and Radiation Physics, University of Wollongong, Australia 13. Ruben Garcia Alia, CERN, Geneva, Switzerland 14. Thomas Berger, Institute of Aerospace Medicine, German Aerospace Center, Germany 15. Marco Durante, GSI Helmholtzzentrum für Schwerionenforschung, Germany 16. Christoph Schuy, GSI Helmholtzzentrum für Schwerionenforschung, Germany

Introduction: Human space exploration beyond low Earth orbit faces challenges in crew health and safety due to radiation from solar particle events (SPEs) and galactic cosmic rays (GCRs). Silicon-on-insulator microdosimetry is useful for biologically relevant dosimetry in mixed radiation fields encountered by astronauts. Their response has been extensively tested in spectral proton fields partially mimicking SPEs, while their response to high Z and energy (HZE) ions has been studied in monoenergetic heavy ion beams only due to an absence of a radiation field mimicking the GCR environment. Method: The GSI Helmholtzzentrum für Schwerionenforschung has developed a GCR-simulator to replicate solar-minimum GCR conditions behind 10 g/cm² of aluminium shielding using primary 56Fe ions of 350, 700, and 1000 MeV/u. Two configurations were used for each energy: ‘slab target’, involving various attenuators and thicknesses, and ‘modulator’, a 3D-printed structure which modulates beam energy. These configurations recreate a GCR-like field. The SOI microdosimeter was exposed to all configurations of the GCR simulator and its response was compared to a tissue equivalent proportional counter (TEPC), a silicon diode, and a silicon based M-42 instrument. Geant4 simulations were employed to compare experimental and simulated spectra. Results: The SOI microdosimeter was able to measure the microdosimetric spectra from 1 to 1000 keV/µm in silicon without pile-up. The measured dose mean lineal energy varied across configurations, demonstrating spectral differences of the field components and their relevant biological efficiency. Conclusion: This is the first ever recreation of a GCR field on European ground and all detectors captured aspects of the GCR field’s complexity, although the range of measured energies by the SOI microdosimeter should be extended to acquire the entire spectrum. This can be achieved by employing a more complex microdosimetric system featuring various sensitive volume thicknesses and gain settings simultaneously.

Presented author:
Pedro Cadamuro Travagin - Universidade de Sao Paulo

Authors:
Pedro Cadamuro Travagin, Department of Physics, FFCLRP, University of Sao Paulo, Av. Bandeirantes, 3900, Ribeirao Preto, SP, 14040-901, Brazil Cassiana Viccari, Department of Physics, FFCLRP, University of Sao Paulo, Av. Bandeirantes, 3900, Ribeirao Preto, SP, 14040-901, Brazil Eldereis de Paula, Department of Physics, FFCLRP, University of Sao Paulo, Av. Bandeirantes, 3900, Ribeirao Preto, SP, 14040-901, Brazil Angela Kinoshita, University of Western São Paulo – Unoeste, R. José Buongiovani, Presidente Prudente, SP, 19050-920, Brazil Patrícia Nicolucci, Department of Physics, FFCLRP, University of Sao Paulo, Av. Bandeirantes, 3900, Ribeirao Preto, SP, 14040-901, Brazil Oswaldo Baffa, Department of Physics, FFCLRP, University of Sao Paulo, Av. Bandeirantes, 3900, Ribeirao Preto, SP, 14040-901, Brazil

Our department recently acquired a self-shielded 137Cs irradiator (Oris Industrie model IBL 637) that was developed for the irradiation of small animals and cell cultures. Since we intend to use this equipment in several applications, repurposing its use, it is necessary to map the dose field throughout the useful space so that different dose rates and volumes to be irradiated can be explored. The irradiator dose surveys are made with TLD, alanine and radiochromic film in different positions of the irradiator where the dose rate is compatible with the dosimeter's use specification. The alanine dosimeter was used in the area closest to the irradiation source, and at greater distances, the TLD and radiochromic film were used. There is a special interest in measuring the dose in the region closest to the source, due to possible that we have inhomogeneities. Since the dose rate in this region is very high, alanine dosimeters were used. Thus, the spatial evaluation of dose delivery in this plane was performed using a matrix (15 x 15 cm) of alanine dosimeters positioned every 1 cm at the base of the irradiator. The matrix received a nominal dose of 400 Gy at its center. In more distant planes, TLD dosimeters and radiochromic films were used. A study of the dose delivered during the movement of the source in the irradiator was also performed. An array of 10 TLD-100 dosimeters was positioned and the movement of the source was activated 10 times. With this information, it was possible to create a map of the dose distribution in the irradiator, which allows for precise irradiation of different samples. Financial Support: CEPID-NEUROMAT, 2013/07699-0, CAPES Finance Code 001 and National Council for Research and Technological Development (CNPq) Grants 305827/2023-5 and 306096/2023-4, and PUB-Fellowship program.

Presented author:
James Vohradsky - University of Wollongong

Authors:
1. James Vohradsky, Centre for Medical and Radiation Physics, University of Wollongong, Wollongong, Australia 2. Matthew Roberts, Centre for Medical and Radiation Physics, University of Wollongong, Wollongong, Australia 3. Linh T. Tran, Centre for Medical and Radiation Physics, University of Wollongong, Wollongong, Australia 4. Vladimir A. Pan, Centre for Medical and Radiation Physics, University of Wollongong, Wollongong, Australia 5. Ilia Filipev, Centre for Medical and Radiation Physics, University of Wollongong, Wollongong, Australia 6. Susanna Guatelli, Centre for Medical and Radiation Physics, University of Wollongong, Wollongong, Australia 7. Naonori Hu, Kansai BNCT Medical Center, Osaka Medical and Pharmaceutical University, Takatsuki, Japan 8. Klaudiusz Jakubowski, Australia Nuclear Science and Technology Organisation, Lucas Heights, Australia 9. Mitra Safavi-Naeini, Australia Nuclear Science and Technology Organisation, Lucas Heights, Australia 10. Anatoly B. Rosenfeld, Centre for Medical and Radiation Physics, University of Wollongong, Wollongong, Australia

Introduction: Boron Neutron Capture Therapy (BNCT) is a binary radiotherapy using 10B(n,a)7Li reaction to kill cancer cells with 10B uptake when irradiated with thermal neutrons. The transition from reactor to accelerator-based neutron production has renewed global interest in BNCT, with 80% of the world’s 33 operational facilities now using accelerator-based systems. Real-time neutron detectors for thermal flux measurements and RBE prediction are essential for advancing BNCT Quality Assurance. Method: Experiments were performed at the Kansai BNCT Medical Center (Osaka, Japan) using the linear array of 5 MOSFETs with pitch 5mm centered in a beam axis and orthogonal to the beam and SOI microdosimeter MicroPlus2 both in a waterproof PMMA sheath, positioned in water using an X-Y motion stage. Both the MOSFETs and the SOI microdosimeters of varying thickness of the cylindrical sensitive volumes (SV) of height 10µm, 5µm and 2µm and diameter 20µm were covered with an enriched 10B carbide film 1µm thickness (equivalent 759,000ppm 10B, with 300µm air gap above SVs), mimicking uptake of 10B on a cell surface. Geant4 Monte Carlo simulations were used to compare with experimental data. Results: Excellent agreement within 5% of measured the thermal neutron flux with MOSFET array vs depth in water with calculated by Monte Carlo has been observed. Microdosimetric spectra are dominated by high lineal energy (very high ppm) 10B fission events peak with yD; 41.04, 81.37, and 148.69 keV/µm corresponding to 10, 5, and 2 µm SOI microdosimeter and in agreement with G4 simulations demonstrating that in 2 µm thick SV most events are crossers. Conclusion: MOSFET and 2 µm thick SOI microdosimeter MicroPlus2 with 10B 1 µm thick converters are promising detectors for QA in BNCT. Next generation of the SOI microdosimeters will be coated with 40-100 ppm 10B during their fabrication.

	Alberto Barajas Celis (ABC) auditorium - Facultad de Ciencias, UNAM
09:30 - 10:00	Invited Talk 8 Hyoungtaek Kim - Korea Atomic Energy Research Institute "Application of luminescence retrospective dosimetry in real small-scale radiological accidents"
10:00 - 11:00	Instrumentation / Detectors I Moderators: Hiroshi Yasuda & Linh Tran
10:00 - 10:15	Neilo Trindade - USP "Development and Characterization of an Integrated System for Thermoluminescence and Radioluminescence Spectroscopy (LUMI-22)"
10:15 - 10:30	Yuriy Zorenko - Kazimierz Wielki University in Bydgoszcz "Composite scintillation detectors as a beneficial tool for dose measurements of secondary radiation in Boron Neutron Capture Therapy"
10:30 - 10:45	Jun Hu - National Institutes for Quantum Science and Technology "Evaluation of coloration-dependent correction method for heavy ion measurements in FNTD"
10:45 - 11:00	Monika Rani - Technical university of Denmark "Visualizing spatial distributions of trapped charge carriers in feldspars with confocal fluorescence microscopy"
11:00 - 12:00	Coffee break
12:00 - 13:30	Instrumentation / Detectors II Moderators: Marcelino Barboza Flores & Miha Furlan
12:00 - 12:15	Tristan Genetay - Lausanne University hospital (CHUV) / CERN "RQR beam qualities measurement with the Timepix4 detector"
12:15 - 12:30	Cheng-Shie Wuu - Columbia University "3D Dosimetry with a Novel Optical CT Scanner using Fiber Optic Taper for Collimated Images "
12:30 - 12:45	Vladimir Pan - UOW "Evaluation of an SOI Microdosimeter for a GCR Simulator at GSI"
12:45 - 13:00	Lily Bossin - Paul Scherrer Institute "Towards a fully automated instrument for the advanced characterisation of radiation-induced luminescence signals: proof-of-concept"
13:00 - 13:15	Pedro Cadamuro Travagin - Universidade de Sao Paulo "Multimodal Dosimetry of a Small Cesium Irradiator"
13:15 - 13:30	James Vohradsky - University of Wollongong "Experimental Evaluation of MOSFET and SOI Microdosimeters for Boron Neutron Capture Therapy Applications"
13:30 - 14:00	Award Ceremony
14:00 - 14:30	Closing Ceremony
20:00 - 21:45	Theatre play Prendida de las lámparas by Elena Guiochins Juan Ruiz de Alarcón theatre, Centro Cultural Universitario, UNAM