Radiation Measurements最新文献

{"title":"Development of a homogeneous thick-walled graphite cylindrical ionization chamber for determination of source strength of HDR 60Co brachytherapy sources","authors":"Sudhir Kumar ,&nbsp;Rahul Kumar Chaudhary ,&nbsp;S.D. Sharma ,&nbsp;B.K. Sapra","doi":"10.1016/j.radmeas.2025.107535","DOIUrl":"10.1016/j.radmeas.2025.107535","url":null,"abstract":"<div><h3>Purpose</h3><div>The source strength of brachytherapy sources should be verified prior to their clinical use. To fulfil the requirement for the standardization of high-dose rate (HDR) ⁶⁰Co brachytherapy sources, a homogeneous thick-walled graphite cylindrical ionization chamber of nominal sensitive volume 223.5 cm³ was designed, developed and established as a reference standard.</div></div><div><h3>Methods</h3><div>Experimental measurements were conducted with HDR ⁶⁰Co brachytherapy sources at different radiotherapy centres across India to determine the basic characteristics of this ionization chamber. The reference air-kerma rate, <span><math><mrow><msub><mover><mi>K</mi><mo>·</mo></mover><mi>R</mi></msub></mrow></math></span>, of the HDR ⁶⁰Co sources was determined from the measured signal using the air-kerma calibration coefficient formalism developed earlier analytically based on Burlin general cavity theory and large cavity theory and validated with Monte-Carlo calculations.</div></div><div><h3>Results</h3><div>The basic characteristics of this chamber were in conformity with requirements specified in IAEA TRS-374 report. The <span><math><mrow><msub><mover><mi>K</mi><mo>·</mo></mover><mi>R</mi></msub></mrow></math></span> of HDR ⁶⁰Co sources determined experimentally using this chamber was within 3 % of the <span><math><mrow><msub><mover><mi>K</mi><mo>·</mo></mover><mi>R</mi></msub></mrow></math></span> value quoted by the supplier, which is traceable to PTB, Germany. The standardized HDR ⁶⁰Co sources were used for calibrating the eight well-type ionization chambers of different radiotherapy centres and the values of air-kerma calibration coefficient <span><math><mrow><msub><mi>N</mi><msub><mover><mi>K</mi><mo>·</mo></mover><mi>R</mi></msub></msub></mrow></math></span> so obtained agreed within 3 % of the vendor-quoted values.</div></div><div><h3>Conclusion</h3><div>The performance of the newly developed chamber was found to be satisfactory and it qualifies to be designated as a reference standard for the measurement of <span><math><mrow><msub><mover><mi>K</mi><mo>·</mo></mover><mi>R</mi></msub></mrow></math></span> of HDR ⁶⁰Co sources and for calibration of the well-type chambers of radiotherapy centres.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"189 ","pages":"Article 107535"},"PeriodicalIF":2.2,"publicationDate":"2025-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145321086","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimization of anti-scatter grids for digital mammography: A comparative study using Monte Carlo simulations","authors":"Kimia Gharehkhani ,&nbsp;Mehdi Shojaei ,&nbsp;Saeed Setayeshi","doi":"10.1016/j.radmeas.2025.107533","DOIUrl":"10.1016/j.radmeas.2025.107533","url":null,"abstract":"<div><div>Mammography image quality is often compromised by scattered radiation, which reduces diagnostic accuracy. Anti-scatter grids with various designs are employed to mitigate this issue. The choice of these designs significantly impacts the reduction of scattered radiation and the transmission of primary photons, thereby improving image quality without necessitating increased patient radiation exposure. This study aims to investigate various anti-scatter grid designs for digital mammography (DM) systems by maximizing the signal-to-noise ratio improvement factor (SIF) and minimizing the scatter-to-primary ratio (SPR) across different material compositions to identify the most effective grid design.</div><div>In this study, a mammography system and breast phantom were simulated using the Monte Carlo toolkit Geant4. A total of 450 cellular anti-scatter grid configurations were modeled, comprising copper, gold, and lead designs with varying grid parameters. The impacts of varying the grid ratios (GR) and strip frequencies on SPR, SIF, and transmission factors for scattered (T_s) and primary (T_p) were quantified. Synthetic mammograms from the Monte-Carlo outputs were generated and contrast-to-noise ratio (CNR) was computed as from paired signal/background region-of-interest (ROI), in the center of the phantom.</div><div>An optimal configuration in our study was a copper grid (GR 3:1, septal thickness 0.005 mm, 35 lines/cm), yielding SIF = 1.09, SPR = 0.06, T_p = 0.75, and T_s = 0.07. Relative to gold and lead, copper grids exhibited higher SIF and T_p; however, gold grids produced the highest CNR (Au ≈ 23.29). Lead grids marginally outperformed gold grids on aggregate transmission/scatter metrics but not on CNR. The proposed grid designs significantly reduced scattered radiation while enhancing image quality metrics, showing promising potential for clinical translation.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"189 ","pages":"Article 107533"},"PeriodicalIF":2.2,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145321085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Flattop leakage dose characterization","authors":"A.S. Tamashiro ,&nbsp;B. Champine ,&nbsp;P. Witter ,&nbsp;P. Maggi ,&nbsp;D.P. Heinrichs ,&nbsp;C. Percher ,&nbsp;D.P. Hickman ,&nbsp;K.L. Jeffers ,&nbsp;R. Radev ,&nbsp;L.I. Tai ,&nbsp;B. Bandong ,&nbsp;T. Classen ,&nbsp;R. Hudson ,&nbsp;D. McAvoy ,&nbsp;J. Scorby ,&nbsp;J. Goda ,&nbsp;T. Cutler ,&nbsp;J.A. Bounds ,&nbsp;D. Hayes ,&nbsp;D. Ward ,&nbsp;M. Baumann","doi":"10.1016/j.radmeas.2025.107531","DOIUrl":"10.1016/j.radmeas.2025.107531","url":null,"abstract":"<div><div>Upon the completion of characterizing the Godiva-IV leakage dose in 2014 and a nuclear accident dosimeter (NAD) intercomparison exercise in 2016, the U.S. Department of Energy (DOE) Nuclear Criticality Safety Program (NCSP) supported an experimental campaign to characterize the Flattop leakage dose in 2017. Two Rotating Neutron Spectrometers (ROSPEC) and a Passive Neutron Spectrometer (PNS) were used to measure the neutron spectra. The neutron spectra were converted to neutron dose using dose conversion factors. CaF<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>:Mn thermoluminescent dosimeters (TLDs), LiF TLDs, and radiophotoluminescence dosimeters were used to measure the photon doses. The data were documented in a report at that time but this paper reanalyzed and updated results. This work established updated reference neutron and photon doses as a function of radial distance from the center of Flattop, which will be used for future NAD intercomparison exercises.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"189 ","pages":"Article 107531"},"PeriodicalIF":2.2,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145220924","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Directional capacity of a two detector array for localization of gamma emitting sources","authors":"Harri Toivonen ,&nbsp;Mark Dowdall ,&nbsp;Sakari Ihantola ,&nbsp;Aliaksandr Dvornik ,&nbsp;Maria Karampiperi ,&nbsp;Robert Finck ,&nbsp;Pernille Ahlmann Jensen ,&nbsp;Gísli Jónsson ,&nbsp;Philip Holm ,&nbsp;Jussi Huikari ,&nbsp;Kari Peräjärvi ,&nbsp;Christopher Rääf ,&nbsp;Viktor Lehmann ,&nbsp;Christian Bernhardsson","doi":"10.1016/j.radmeas.2025.107534","DOIUrl":"10.1016/j.radmeas.2025.107534","url":null,"abstract":"<div><div>Capacities for source localization in response to incidents involving radioactive materials are essential for effective, efficient response. In this context, the directional response of a detection system is of importance. Many solutions currently employed for source localization involve approaches that may be onerous with respect to cost, complexity and practicality for field operations. To avoid these drawbacks, an approached was developed based on simultaneous use of two gamma detectors (2 x 1 array). Simple mathematical models were developed to cope with the count rate detected by two adjacent detectors. The parameters of the model depend mainly on the design of the detectors and can thus be concluded from the drawings. For large detectors, the energy dependency of the directional estimate is negligible. The method can be applied for small hand-held systems as well without resort to complex calibrations or data processing. The directional response of several 2 x 1 arrays, constructed from commercially available, off-the-shelf detectors, was confirmed using Monte Carlo approaches and actual measurements under controlled conditions. Optimization strategies and performance constraints were described and analyzed regarding the use of a shield between the detectors. Results indicate that 2 x 1 arrays of a number of detector types and sizes can provide functional estimates of source direction a field of view of 180°.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"189 ","pages":"Article 107534"},"PeriodicalIF":2.2,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145220925","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Calculation and verification of energy deposition by high-energy deuterons in thick beryllium target","authors":"Zhichao Gao ,&nbsp;Xueying Zhang ,&nbsp;Yongqin Ju ,&nbsp;Rui Han ,&nbsp;Honglin Ge ,&nbsp;Fei Ma ,&nbsp;Yanbin Zhang ,&nbsp;Bin Zhou ,&nbsp;Liang Chen ,&nbsp;GuoYu Tian ,&nbsp;Tao Wan ,&nbsp;Yaoxuan Cui ,&nbsp;Wenli Qu","doi":"10.1016/j.radmeas.2025.107530","DOIUrl":"10.1016/j.radmeas.2025.107530","url":null,"abstract":"<div><div>The d-Be neutron source is a compact accelerator neutron source with significant potential. The energy deposition of a high-energy deuteron beam in beryllium target serves as an important reference consideration in the design of target heat removal systems. The total energy deposition of deuterons, energy deposition linear density, and the contributions of different secondary particles in thick beryllium targets is investigated using Geant4 toolkit with three reaction models. Additionally, we conducted an experiment of a 300 MeV deuteron beam bombarding thick beryllium targets, where multiple thermoluminescent detectors were used to measure the dose distribution in targets. The comparison between simulation results and experimental data indicate that the Geant4 simulation effectively estimates the energy deposition of the d-Be reactions, with the BIC_AllHP model showing the best agreement with the experimental data.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"189 ","pages":"Article 107530"},"PeriodicalIF":2.2,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145267673","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental evaluation of radon detector performance under controlled conditions: Statistical assessment and calibration strategy","authors":"A. Noverques,&nbsp;B. Juste,&nbsp;C. Trull-Hernandis,&nbsp;G. Verdu","doi":"10.1016/j.radmeas.2025.107532","DOIUrl":"10.1016/j.radmeas.2025.107532","url":null,"abstract":"<div><div>This work presents a quantitative evaluation of radon detectors under controlled environmental conditions using the RDN-SENUBIO-UPV radon chamber. The study emphasizes the statistical assessment of spatial radon distribution and the comparative sensitivity analysis of multiple detector models against a high-precision AlphaGUARD monitor. A comprehensive methodology is developed, involving the calculation of relative errors, analysis of variance (ANOVA), and normality testing (Kolmogorov–Smirnov), to assess measurement consistency. Moreover, individual correction factors are derived and validated through repeated experimental trials to improve the accuracy of time-dependent measurements. The proposed calibration protocol enhances measurement reliability by accounting for detector-specific response dynamics and environmental transients. The results support the implementation of reproducible correction schemes and contribute to improved quality assurance practices in radon monitoring. The approach provides a rigorous statistical framework applicable to other radiation detection systems.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"189 ","pages":"Article 107532"},"PeriodicalIF":2.2,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145159090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling the stochastic-deterministic boundary in luminescence: Consequences for dose estimation","authors":"Eren Şahiner","doi":"10.1016/j.radmeas.2025.107529","DOIUrl":"10.1016/j.radmeas.2025.107529","url":null,"abstract":"<div><div>Kinetic models based on deterministic ordinary differential equations (ODEs) are effective for macroscopic systems, but a breakdown of their foundational assumptions is observed for single-grain and nanodosimetric applications where particle numbers are small. In this study, the metrological consequences of this stochastic-deterministic divergence are quantitatively investigated. The study's primary contribution is to deconvolve the divergence into two distinct components: a robust, inherent imprecision and a model-dependent, systematic inaccuracy. Intrinsic physical stochasticity is confirmed to be a dominant source of imprecision, generating an irreducible dose uncertainty of over 20 % that accounts for a significant fraction of single-grain overdispersion. Conversely, a systematic inaccuracy (e.g., a &gt;50 % dose bias), initially observed in a simplified model, is demonstrated to be a methodological artifact, not a universal consequence of discreteness. It is shown that this systematic bias can be reduced to negligible levels (&lt;1 %) by using either a more physically realistic multi-trap model or a correctly specified simple model. Based on this deconvolution, analytical protocols are assessed. An \"Average-Dose-First\" protocol is identified as the superior method, as it provides an accurate final dose estimate while correctly propagating measurement uncertainty. A general framework for understanding and partitioning variance in luminescence data is thereby established. Practical recommendations are provided for improving the accuracy of modern luminescence science by selecting appropriate models and using correct statistical protocols, with a strong emphasis on the critical need for model validation.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"189 ","pages":"Article 107529"},"PeriodicalIF":2.2,"publicationDate":"2025-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145119384","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Application of deep learning-based track detection technique in neutron personal dose monitoring research","authors":"Yuji Miao ,&nbsp;Wei Chen ,&nbsp;Lu Tian ,&nbsp;Xiaodong Shi ,&nbsp;Yuanyuan Zhou ,&nbsp;Xiangyong Fan ,&nbsp;Jiayi Ma ,&nbsp;Jin Wang","doi":"10.1016/j.radmeas.2025.107526","DOIUrl":"10.1016/j.radmeas.2025.107526","url":null,"abstract":"<div><div>This study introduces the application of the object detection paradigm (Faster R-CNN) to fast neutron track detection using deep learning algorithms. Neutron dose measurements were conducted using CR-39 detectors, and two methods-morphological features-based detection and deep learning (Faster R-CNN) were evaluated. The deep learning method demonstrated superior accuracy, particularly in identifying small tracks and impurity points, achieving a correct-count rate of 98.7 %. Additionally, it significantly improved detection speed compared to manual and morphological feature-based methods. The performance of the neutron personal dosimetry system, which incorporates the deep learning approach, was validated through linearity validation, coefficient of variation analysis, and dose verification. Due to its fully automated nature, this method can reduce measurement uncertainty and can be extended to recognize other types of particle tracks.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"189 ","pages":"Article 107526"},"PeriodicalIF":2.2,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145220923","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Copper-based halide Cs3Cu2I5: (X) bulk single crystals: Growth and applications","authors":"Jianjia Li,&nbsp;Yunfei Ren,&nbsp;Zhicheng Wang,&nbsp;Xiaoming Li","doi":"10.1016/j.radmeas.2025.107527","DOIUrl":"10.1016/j.radmeas.2025.107527","url":null,"abstract":"<div><div>Low-dimensional copper-based halides have garnered wide attention due to their strong self-trapped exciton (STE) emission, among which, Cs₃Cu₂I₅ (CCI), characterized by a zero-dimensional electronic structure, exhibits promising application potential across multiple fields owing to its non-toxicity and excellent environmental stability. Notably, its exceptional radioluminescence properties make it an outstanding scintillator material for high-energy radiation detection. In recent years, although reports on diverse CCI material morphologies abound, bulk single crystals have become the primary focus because of their superior light output and low defect density. In this review, we systematically summarize and discuss the growth methodologies and applications of CCI bulk single crystals, which encompasses both melt and solution growth techniques, as well as currently developed and potentially superior application scenarios. Furthermore, we dedicate a section to discuss doping engineering strategies applied to CCI materials and the resultant property enhancements. Finally, the key challenges and future research directions for CCI bulk single crystals are outlined.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"189 ","pages":"Article 107527"},"PeriodicalIF":2.2,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145159089","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Radiation source analysis of beamline stations at fourth-generation synchrotron light facility","authors":"Jiaduo Chen ,&nbsp;Shiping Jiang ,&nbsp;Penghui Yang ,&nbsp;Lin Wang","doi":"10.1016/j.radmeas.2025.107528","DOIUrl":"10.1016/j.radmeas.2025.107528","url":null,"abstract":"<div><div>Bremsstrahlung produced by electrons in the storage ring is a major concern in the radiation shielding design of synchrotron light sources, primarily arising from the Touschek effect and vacuum-related effect. Depending on the underlying mechanism, the resulting bremsstrahlung is classified as either solid or gas bremsstrahlung, both of which can propagate into beamline stations, especially from straight sections, thereby posing radiological risks to personnel and equipment.</div><div>With the advancement of fourth-generation synchrotron light sources based on diffraction-limited storage ring technology, the characteristics of bremsstrahlung radiation originating from straight sections have become increasingly complex, making earlier radiation source models no longer directly applicable. The objective of this study is to conduct an analysis of radiation sources in beamline stations of fourth-generation synchrotron facilities, clarify their respective contributions, and evaluate the implications of different modeling methodologies for shielding design. This study focuses on a representative beamline at the Hefei Advanced Light Facility. Three modeling approaches are developed and compared: (i) a simplified model, which assumes uniform electron losses throughout the storage ring with fixed-angle impacts on internal surfaces; (ii) a more refined model, which uses ELEGANT to accurately simulate electron loss positions and dynamics in straight sections, coupled with FLUKA to analyze the generation and transport of solid bremsstrahlung; and (iii) a gas bremsstrahlung model, which employs FLUKA to directly simulate electron–residual gas interactions.</div><div>The study compares the energy spectra, angular distributions, and spatial profiles of bremsstrahlung from the three models on the upstream wall of the first optical enclosure. Ambient dose equivalent distributions surrounding the enclosure are also evaluated. Results indicate that both solid and gas bremsstrahlung are major contributors to radiation levels in the beamline stations, each exhibiting distinct spatial and spectral characteristics. In addition, the study finds that the simplified model introduces significant deviations in the estimation of solid bremsstrahlung, highlighting the importance of accurately incorporating electron loss information in radiation simulations for beamline stations at fourth-generation synchrotron light sources to achieve reliable shielding assessments.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"189 ","pages":"Article 107528"},"PeriodicalIF":2.2,"publicationDate":"2025-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145097124","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}