Radiation Measurements最新文献

{"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":"2025-12-01","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}

{"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":"2025-12-01","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":"Application of a PGNAA-based neutron spectrometer for simulated workplace neutron field measurement","authors":"Can Cheng ,&nbsp;Liteng Xing ,&nbsp;Jiayu Gu ,&nbsp;Jiatong Li ,&nbsp;Zeliang Wang ,&nbsp;Zhenhua Zhang ,&nbsp;Daqian Hei ,&nbsp;Wenbao Jia ,&nbsp;Ruoyu Chen ,&nbsp;Xunrong Xia ,&nbsp;Chuanhui Yuan","doi":"10.1016/j.radmeas.2025.107544","DOIUrl":"10.1016/j.radmeas.2025.107544","url":null,"abstract":"<div><div>The calibration of neutron dosimeter needs to be conducted in a neutron field that closely resembles its workplace field. Neutron generators can be used to simulate the workplace neutron field, making the measurement of the neutron spectrum in the modulated field a crucial task. In this study, a neutron spectrometer based on prompt gamma ray neutron activation analysis (PGNAA) was employed to measure the neutron spectrum. The response of the neutron spectrometer was calculated using Monte Carlo simulation, and benchmark measurements were carried out in D-D and D-T neutron fields. The results show that the energy responses at 2.5 MeV and 14 MeV are in good agreement with the simulated values. The neutron spectrum of a graphite-moderated D-D neutron source was unfolded using the neutron spectrometer and the corresponding neutron ambient dose equivalent rate was compared with the value recorded by neutron dosimeter. The deviation between the two is 14 %, validating the feasibility of the neutron spectrometer and its potential application for neutron dosimeter calibration.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"189 ","pages":"Article 107544"},"PeriodicalIF":2.2,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145363312","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 investigation of a heatless approach for initializing radiophotoluminescence glasses (FD-7) using ultraviolet light","authors":"Soheil Aghabaklooei ,&nbsp;Hiroshi Yasuda","doi":"10.1016/j.radmeas.2025.107525","DOIUrl":"10.1016/j.radmeas.2025.107525","url":null,"abstract":"<div><div>Ag-doped phosphate radiophotoluminescence (RPL) glass dosimeter (RPLD) is widely used for radiation dosimetry. Although RPLD has the advantage of reusability through proper annealing, the current annealing process has undesirable features, such as heating at a high temperature (approximately 400 °C) and subsequent long (nearly half a day) cooling. In this study, we propose a new approach to initialize RPLDs more safely and rapidly using ultraviolet light (UV), which is expected to be preferable in many occasions, including quality assurance (QA) for radiotherapy. Four samples of commercially available RPLD glass (FD-7) with a size of φ1.5 mm × 12 mm were irradiated with X-rays (160 kV, 6.3 mA) at 0.1, 0.5, 1, 2, and 5 Gy (for H₂O) and exposed to UV from a high-pressure mercury UV lamp, which has a broad wavelength range with a dominant peak at 365 nm. RPL intensities were measured using an exclusive RPL readout system (FDG-1000, Asahi Techno Glass Co., Ltd.) at certain time intervals at room temperature. After 3-h UV exposure, the RPL intensity decreased by &gt;90 % for irradiation of 1 Gy or higher, and 6-h UV exposure cleared &gt;95 % of the RPL intensity for 2 Gy or higher. The RPL intensity increased slightly (2 % in 24 h at room temperature) after the termination of UV exposure. According to these findings, it is expected that the proposed heatless approach to initialize RPLDs, named ‘UV-annealing method’ here, will be effectively applied to routine dosimetry in relatively high-dose radiation fields, including radiotherapy facilities.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"189 ","pages":"Article 107525"},"PeriodicalIF":2.2,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145047642","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":"Characterization of low-energy protons by fluorescent nuclear track detectors based on lithium fluoride films on silicon substrates","authors":"Massimo Piccinini ,&nbsp;Enrico Nichelatti ,&nbsp;Valentina Nigro ,&nbsp;Adriano Zerbini ,&nbsp;Rosa Maria Montereali ,&nbsp;Concetta Ronsivalle ,&nbsp;Alessandro Ampollini ,&nbsp;Maria Aurora Vincenti","doi":"10.1016/j.radmeas.2025.107547","DOIUrl":"10.1016/j.radmeas.2025.107547","url":null,"abstract":"<div><div>In the last years, Fluorescent Nuclear Track Detectors (FNTDs) based on the visible radiophotoluminescence (RPL) of aggregate F₂ and F₃⁺ color centers (CCs) in lithium fluoride (LiF) crystals have been demonstrated. On the other hand, optically transparent polycrystalline LiF thin films, grown by thermal evaporation on Si(100) substrates, have been successfully used for proton beam advanced diagnostics, mainly through Bragg curve permanent recording and analysis. In this paper, they were tested as FNTDs for low-energy, nearly monochromatic, collimated proton beams produced by the vertical low-energy extraction line of the TOP-IMPLART proton linear accelerator in operation at ENEA Frascati, Italy. Cleaved LiF films were irradiated with the film plane approximately parallel to the beam propagation direction and the film edge directly exposed to the incident beam. The irradiation caused the formation of CCs along the proton tracks within the film. The luminescent track images were visualized with a fluorescence microscope under blue LED excitation. At the lower energy of ∼1 MeV, it was possible to record single entire proton tracks at a fluence of approximately 10⁸ protons/cm². Their lengths are comparable with those expected in the LiF film. Increasing the proton energy to ∼6 MeV, the luminescent tracks were observed mainly close to the expected Bragg peak position, i.e., at the penetration depth where it would be found in Si rather than in LiF, due to multiple Coulomb scattering. At both energies, by raising the fluence by two orders of magnitude, the superposition of a very high number of tracks allowed recording the luminescent Bragg curves of the proton beams in the LiF films. They were analyzed using two different methods, considering also the type of substrate and the film characteristics, allowing to estimate the beam energy spectrum. At ∼1 MeV, the Bragg curve was best fitted using a random-optimization approach, while at ∼6 MeV it was reproduced using depth-dose curves simulated in FLUKA.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"189 ","pages":"Article 107547"},"PeriodicalIF":2.2,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145416912","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":"2025-12-01","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":"Using neutron-neutron angular correlation as a complementary observable in the fast neutron multiplicity counting for low-quality nuclear materials","authors":"Kaile Li,&nbsp;Peng Xu,&nbsp;Sufen Li,&nbsp;Jiangyu Yan","doi":"10.1016/j.radmeas.2025.107541","DOIUrl":"10.1016/j.radmeas.2025.107541","url":null,"abstract":"<div><div>In the process of nuclear fission, due to the momentum enhancement of the fission fragments, the neutrons will exhibit angular correlation. For a certain class of problem the emergent n-n angular correlation trends with multiplication. Using the scintillation array can simultaneously obtain time and angle information of fission neutrons. Therefore, this paper make an exploratory study of the potential of using neutron-neutron angular correlation as a complementary observable in the fast neutron multiplicity counting. This paper explores the intrinsic relationship between neutron anisotropy and multiplication coefficient, and neutron anisotropy can be used as a reference to reflect multiplication coefficient On this basis, the fission neutron anisotropy was quantified with the ratio of neutron–neutron coincidences observed at 180° and 90°. Fitting the neutron leakage multiplication coefficient and anisotropy. After measuring the anisotropy of the sample, the leakage multiplication coefficient can be obtained through this fitting relationship, and then combine it with fast neutron multiplicity to solve the mass of nuclear material,. The results were verified through simulation calculations by Geant4. The deviation of the results obtained by using this method is significantly lower than that obtained by using the fast neutron multiplicity method. This method can be used for estimate the quality properties of nuclear materials, but is not intended for the assay of completely unknown items. Instead, we reframe its potential application for situations where a item's general class is known.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"189 ","pages":"Article 107541"},"PeriodicalIF":2.2,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145363311","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":"Utilizing the coincidence and anti-coincidence counting of crosstalk events to enhance measurement accuracy in BNCT-SPECT","authors":"Yu Fujiwara,&nbsp;Mana Miyagawa,&nbsp;Mikito Yagura,&nbsp;Jiye Qiu,&nbsp;Shingo Tamaki,&nbsp;Sachie Kusaka,&nbsp;Fuminobu Sato,&nbsp;Isao Murata","doi":"10.1016/j.radmeas.2025.107538","DOIUrl":"10.1016/j.radmeas.2025.107538","url":null,"abstract":"<div><div>Single Photon Emission Computed Tomography (SPECT) in Boron Neutron Capture Therapy (BNCT) plays a vital role in real-time monitoring of treatment effects. However, image quality can be degraded by background noise. We propose a novel noise-reduction technique that utilizes both coincidence and anti-coincidence counting methods, leveraging the crosstalk phenomenon between adjacent scintillators. To evaluate the feasibility of this approach, we measured γ-ray spectra from a¹³⁷Cs standard source using two GAGG scintillators. The results showed noise reduction improvements of 15.9 % with coincidence and 3.8 % with anti-coincidence methods. Additionally, theoretical analysis demonstrated that this approach is effective in multiple scintillators arranged by the forward nature of Compton Scattering. This approach offers a promising path toward improving BNCT-SPECT imaging quality by effectively discriminating target signals from noise in high-density detector arrays.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"189 ","pages":"Article 107538"},"PeriodicalIF":2.2,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145363314","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":"Exploring the correlation between thermoluminescence and optically stimulated luminescence of rose quartz","authors":"I.A. Ferreira ,&nbsp;E.M. Yoshimura ,&nbsp;N.M. Trindade","doi":"10.1016/j.radmeas.2025.107543","DOIUrl":"10.1016/j.radmeas.2025.107543","url":null,"abstract":"<div><div>This work investigates the correlation between thermoluminescence (TL) and optically stimulated luminescence (OSL) signals in natural rose quartz. Four distinct TL glow peaks were identified at 90 °C (I), 140 °C (II), 215 °C (III), and 336 °C (IV) at a heating rate of 1 °C/s. The effect of blue LED illumination on TL glow peaks was investigated revealing a systematic reduction in the intensity of peaks I-III. Additionally, the influence of the temperature on the OSL decay curve characteristics was analyzed, showing a marked decrease in the OSL signal at temperatures above 100 °C. These results contribute to understanding the thermal and optical behavior of rose quartz, with implications for its use in radiation dosimetry.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"189 ","pages":"Article 107543"},"PeriodicalIF":2.2,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145416880","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":"2025-12-01","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}