Radiation Measurements最新文献

{"title":"Isolated radiation damage created along un-etchable tracks in PADC consists of two hydroxyl groups","authors":"Tomoya Yamauchi ,&nbsp;Reo Yamada ,&nbsp;Atsushi Kimoto ,&nbsp;Hayato Seiichi ,&nbsp;Shunto Sadamitsu ,&nbsp;Daisuke Kohinata ,&nbsp;Masato Kanasaki ,&nbsp;Ichiro Sasaki ,&nbsp;Shigeki Watanabe ,&nbsp;Noriko S. Ishioka ,&nbsp;Nobumasa Miyawaki","doi":"10.1016/j.radmeas.2025.107491","DOIUrl":"10.1016/j.radmeas.2025.107491","url":null,"abstract":"<div><div>The objective of the present work is to clarify the damage structure along un-etchable tracks in PADC, by determining the damage density of ether as well as the formation density of hydroxyl group along them. Both the damage density and the formation density have been evaluated by means of FT-IR spectrometry on PADC films before and after the exposures to 30 MeV and 65 MeV proton beams with various fluence. The ratio of the damage density of ether to the formation density of hydroxyl group was about 1:2, which was almost identical to those for protons and He ions with energies of below 6 MeV/u. Futhermore, the ratio was hardly changed even in the case of in vacuum irradiation, where the formation density of hydroxyl group was suppressed. It can be assumed that damage consisting of two isolated hydroxyl groups within a single repeating unit of PADC is hardly to alter its etching properties. The stable and high density formation of such specific damage would enable the development of more sensitive detectors.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"187 ","pages":"Article 107491"},"PeriodicalIF":1.6,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144665606","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":"First study of X-ray radiation in 45 MW klystrons via Monte Carlo simulations and in situ measurements","authors":"Xirui Zhou ,&nbsp;Yao Yang ,&nbsp;Kuangkuang Ye ,&nbsp;Lei Yang ,&nbsp;Junqiang Zhang ,&nbsp;Xue Yang ,&nbsp;Hanshang Lin ,&nbsp;Zhongquan Li","doi":"10.1016/j.radmeas.2025.107484","DOIUrl":"10.1016/j.radmeas.2025.107484","url":null,"abstract":"<div><div>High-power klystrons are essential for generating microwave signals that accelerate charged particles. However, their operation at such high-power levels, typically the average power ranging from several kilowatts to megawatts, raises concerns regarding unintended X-rays production. This investigation focuses on characterizing the X-ray spectrum and dose equivalent rate generated during high-power test conditions before official operation. Using Monte Carlo simulations, the generation and penetration of X-rays are analyzed. Through detection systems, we analyzed the dose rate distributions of X-rays at various locations of the klystron. The energy of X-rays is obtained by shielding attenuation method. The results indicate that significant X-rays production occurs primarily due to the Bremsstrahlung process, which is associated with high-energy electron impacts on the klystron components. The findings reveal that, while the dose rates remain within regulatory safety limits, radiation monitoring and enhanced local shielding are suggested for ensuring the safety of personnel when working close to the klystron.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"187 ","pages":"Article 107484"},"PeriodicalIF":1.6,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144662091","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":"Assessing quartz luminescence sensitivity protocols for fine-grained sediments in marine sediment cores","authors":"Priscila E. Souza ,&nbsp;André O. Sawakuchi ,&nbsp;Dayane B. Melo ,&nbsp;Fernanda C.G. Rodrigues ,&nbsp;Cristiano M. Chiessi ,&nbsp;Stefan Mulitza ,&nbsp;Vinícius R. Mendes","doi":"10.1016/j.radmeas.2025.107490","DOIUrl":"10.1016/j.radmeas.2025.107490","url":null,"abstract":"<div><div>Applications of quartz luminescence beyond sediment dating are expanding rapidly. A growing number of studies have successfully applied quartz optically stimulated luminescence (OSL) and thermoluminescence (TL) sensitivities in sediment provenance investigations and palaeoclimate reconstructions based on marine sediment cores, which are usually composed of fine-grained sediments (silt and clay), demanding measurements on polymineral samples. However, the procedures during sample preparation and the luminescence measurement conditions for determining the quartz OSL and TL sensitivities of fine-grained polymineral samples have not yet been extensively assessed. Here, we present the results of five different tests designed to determine whether the current procedures employed when preparing the samples and measuring their quartz luminescence sensitivities could be improved and/or simplified. The tests include assessing the dependency of quartz OSL and TL sensitivities on: (1) luminescence measurement conditions (i.e., with and without preheat, with light stimulation at room temperature and at 125 °C, based on natural and laboratory dose); (2) aliquot mass; (3) number of aliquots per sample; (4) grain size selection; and (5) feldspar content. Tests were performed on polymineral fine sediments from two marine cores, GeoB16206–1 and M78/1-235-1, recovered from the western equatorial Atlantic, close to the mouth of the Parnaíba and Orinoco rivers, respectively. In general, our results show that the procedures when preparing polymineral aliquots for quartz OSL or TL sensitivity measurements can be easily optimized on a case-by-case basis, saving time and resources. Our key result is that quartz OSL sensitivity obtained using natural signals and measured without thermal treatments (Test 1) are very similar to the results obtained using regenerative doses and preheating. This opens the possibility of reducing the OSL measurement time by 70 % and of scanning marine sediment cores with portable luminescence readers without the use of radiation sources for signal regeneration. Tests 2 and 3 show that both OSL and TL sensitivity results given by more than six aliquots or by aliquots made of 0.4 mg to 5 mg are indistinguishable. Waiting longer settling times to subsample finer fractions before mounting the aliquots (Test 4) is helpful to reduce feldspar, but it may also reduce the quartz significantly, limiting the %BOSL_1s analysis. Finally, including an etching step to reduce feldspar (Test 5) is a helpful procedure to improve the TL and OSL sensitivity analysis, but not necessarily feasible for routine application with hundreds of samples.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"187 ","pages":"Article 107490"},"PeriodicalIF":1.6,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144653881","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":"Assessment of experimental parameters influence on radon concentration in systems with air-water contact","authors":"A. Noverques,&nbsp;B. Juste,&nbsp;M. Sancho,&nbsp;G. Verdú","doi":"10.1016/j.radmeas.2025.107489","DOIUrl":"10.1016/j.radmeas.2025.107489","url":null,"abstract":"<div><div>Radon is a naturally occurring radioactive gas, considered the first lung cancer cause in non-smokers. The significant environmental and health implications are often studied in systems where water and air phases interact. Accurate modeling of radon behavior is critical in laboratory research context. However, deviation in experimental setups can increase uncertainties in radon knowledge.</div><div>This study investigates the influence of key experimental parameters on radon concentration in systems with air-water contact. Specifically, the study evaluates the impact of water sampling points, the sampling method and the total water volume within the setup.</div><div>The experimental results demonstrate there are no significant variations in the behavior of radon gas diffusion as similar concentration values and accumulation trends are observed regardless of the experimental setup. This research confirms that changes in these experimental conditions do not compromise radon transport coefficients and models obtained in previous work.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"187 ","pages":"Article 107489"},"PeriodicalIF":1.6,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144605207","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":"Method of deriving the response curve of an ionisation chamber from experimental values of its air kerma calibration coefficients measured in standardised X-ray beams","authors":"Libor Judas,&nbsp;Dana Kurková","doi":"10.1016/j.radmeas.2025.107488","DOIUrl":"10.1016/j.radmeas.2025.107488","url":null,"abstract":"<div><div>Air-equivalent ionisation chambers are the reference instruments for measuring air kerma in dosimetry calibration laboratories. The energy dependence of the response of a given ionisation chamber is usually characterised by a discrete set of values of its air kerma calibration coefficients, <em>N</em>_<em>K,a</em>, measured in standardised photon beams. For photon energies below 300 keV, the most commonly used standardised calibration beams are the X-ray beams, i.e. beams with continuous spectra.</div><div>The energy dependence of a given ionisation chamber could alternatively be characterised by the response function <em>f</em>_<em>IK</em><em>(E)</em> which describes the dependence of the magnitude of the electrical response of the chamber on the photon energy, <em>E</em>, at a constant air kerma rate. In practice, this method of characterising the energy dependence of the ionisation chamber response is rarely used because monoenergetic calibration photon beams covering the above mentioned energy range are not routinely available and it is therefore difficult to measure the response function <em>f</em>_<em>IK</em><em>(E)</em> experimentally.</div><div>In this work, we show that:</div><div>a) the response function <em>f</em>_<em>IK</em><em>(E)</em> of a given ionisation chamber can be derived from the values of its air kerma calibration coefficients, <em>N</em>_<em>K,a</em>, measured in standardised X-ray calibration beams;</div><div>b) the proposed method can reveal possible internal inconsistencies in the set of air kerma calibration coefficients, <em>N</em>_<em>K,a</em>, of an ionisation chamber;</div><div>c) the response function <em>f</em>_<em>IK</em><em>(E)</em> of a given ionisation chamber derived from a set of its <em>N</em>_<em>K,a</em> values can be used to predict the <em>N</em>_<em>K,a</em> values of the chamber for other X-ray beams.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"187 ","pages":"Article 107488"},"PeriodicalIF":1.6,"publicationDate":"2025-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144679339","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":"Light emission from uniformly irradiated rectangular cuboid scintillators","authors":"Benoit Lefebvre ,&nbsp;Lorenzo Sostero ,&nbsp;Roberto Versaci ,&nbsp;Veronika Olšovcová","doi":"10.1016/j.radmeas.2025.107485","DOIUrl":"10.1016/j.radmeas.2025.107485","url":null,"abstract":"<div><div>Scintillator arrays are widely used in radiation detection, but imaging these arrays with a camera can introduce point-of-view (POV) effects. To better understand these effects, we present a model for light transport within scintillators shaped like a rectangular cuboid. Analytical expressions for the light projection are derived, and the impact of surface roughness is investigated using Monte Carlo simulations. Finally, benchmark measurements using bismuth germanate (BGO) scintillators validate the model’s predictions.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"187 ","pages":"Article 107485"},"PeriodicalIF":1.6,"publicationDate":"2025-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144588553","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":"Detection of beta-emitting radioactive hotspots inside the Fukushima Daiichi Nuclear Power Station Unit 3 reactor building using an optical fiber radiation sensor based on wavelength-resolving analysis","authors":"Yuta Terasaka ,&nbsp;Yuki Sato ,&nbsp;Yuta Ichiba","doi":"10.1016/j.radmeas.2025.107486","DOIUrl":"10.1016/j.radmeas.2025.107486","url":null,"abstract":"<div><div>We measured the distribution of beta-ray emitters inside the Fukushima Daiichi Nuclear Power Station Unit 3 reactor building using a novel optical fiber-based position-sensitive radiation sensor designed for operation in high dose rate environments. Plastic scintillation fibers (PSFs) were installed inside the Unit 3 reactor building, where scintillation light generated through interactions between radiation and the PSFs was detected by a spectrometer to obtain the wavelength spectrum. By applying an unfolding method to the wavelength spectrum, we estimated the distribution of beta ray emitters along the PSFs. To isolate the beta ray contribution in a high gamma dose rate field, we compared measurements taken with and without a stainless steel tube serving as a beta ray shield. As a result, we identified a hotspot predominantly influenced by beta rays for the first time in the high dose rate area on the southern side of the first floor of the Unit 3 reactor building.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"187 ","pages":"Article 107486"},"PeriodicalIF":1.6,"publicationDate":"2025-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144516904","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":"Applying a bicorrelation method for determining the angular correlation of gamma-rays using gamma–gamma coincidence","authors":"Brandon De Luna ,&nbsp;Kevin Smith ,&nbsp;Stefan Marin ,&nbsp;Sheldon Landsberger","doi":"10.1016/j.radmeas.2025.107481","DOIUrl":"10.1016/j.radmeas.2025.107481","url":null,"abstract":"<div><div>The angular correlation between two coincident gamma ray pairs from ¹⁵²Eu was found at multiple distances (1–13 cm) and detector orientations (180-30°). This phenomenon was extrapolated from calculated bicorrelation coefficients observed from the 344 keV + 778 keV coincident gamma rays from <span><math><msup><mrow><mi>β</mi></mrow><mrow><mo>−</mo></mrow></msup></math></span> decay and the 121 keV + 244 keV coincident gamma rays from electron capture. The angular correlation for the electron capture gamma ray pair was determined to be higher when the detectors were at or close to 180 ° (facing each other) whereas the angular correlation for the <span><math><msup><mrow><mi>β</mi></mrow><mrow><mo>−</mo></mrow></msup></math></span> decay gamma ray pair was higher when the angle between detectors approached 90° (perpendicular). The results of this work highlight the utility of tuning measurements utilizing a radioactive species’ angular correlation of coincidence gamma ray pairs to maximize the counting statistics for specific radionuclides such as those observed through neutron activation analysis.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"187 ","pages":"Article 107481"},"PeriodicalIF":1.6,"publicationDate":"2025-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144481646","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":"Updating internal dosimetry coefficients of I-131 based on new mesh-type computational phantoms of adult male and female using the DoseCalcs platform","authors":"Tarik El Ghalbzouri ,&nbsp;Tarek El Bardouni ,&nbsp;Jaafar El Bakkali","doi":"10.1016/j.radmeas.2025.107479","DOIUrl":"10.1016/j.radmeas.2025.107479","url":null,"abstract":"<div><div>The use of radionuclides in nuclear medicine, both for diagnostic and therapeutic purposes, represents a cornerstone of modern cancer treatment, particularly when utilizing iodine-131. When iodine-131 is administered, it is designed to specifically target the thyroid gland, delivering maximum radiation energy to the tumor. However, iodine-131 circulates through the bloodstream and reaches various regions in the body, exposing them to radiation. In this context, accurate dosimetry calculations are essential to ensure both the safety and efficacy of the treatment.</div><div>We used the latest mesh-type phantom generations to update existing S-values derived from stylized and voxel-based phantoms, leveraging the enhanced anatomical representation of organs/tissues in the latest phantom models.</div><div>To perform the simulations, we used the Monte Carlo-based DoseCalcs platform, in which we implemented anatomical characteristics such as shape data and chemical composition of regions provided by ICRP Publication 145 and radiation data of I-131 from ICRP Publication 107 to simulate the transport of radiation emitted by I-131 and calculate the corresponding S-values for several source-organ combinations.</div><div>We calculated I-131 S-values for nine source regions and twenty-eight target regions using mesh-type phantoms of adult male and female. When comparing these values with those calculated using voxel-based phantoms, we observed that the two datasets were generally similar for most target<span><math><mo>←</mo></math></span>source combinations. However, notable differences were identified, particularly for distant combinations (e.g., brain <span><math><mo>←</mo></math></span> urinary bladder contents) and adjacent regions such as content and wall combinations. In some cases, the ratio reached up to 4 (e.g., stomach wall <span><math><mo>←</mo></math></span> stomach contents, urinary bladder wall <span><math><mo>←</mo></math></span> urinary bladder contents).</div><div>These results underscore the impact of geometric modifications in mesh-type phantoms, particularly for wall regions, where anatomical representations differ significantly from voxel-based phantoms.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"187 ","pages":"Article 107479"},"PeriodicalIF":1.6,"publicationDate":"2025-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144489557","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":"Neutron-gamma discrimination method based on voiceprint identification","authors":"Kuo Zhao ,&nbsp;Han Wang ,&nbsp;Xiao-Tian Wang ,&nbsp;Liao-Hui An ,&nbsp;Liang Chen ,&nbsp;Ya-Peng Zhang ,&nbsp;Ning Lv ,&nbsp;Yang Li ,&nbsp;Jin-Lu Ruan ,&nbsp;Shi-Yi He ,&nbsp;Lei-Dang Zhou","doi":"10.1016/j.radmeas.2025.107483","DOIUrl":"10.1016/j.radmeas.2025.107483","url":null,"abstract":"<div><div>Aiming at the limited prior knowledge from the pulsed neutron radiation field, a new method for neutron/gamma pulse shape discrimination (PSD) is proposed based on the theory of Voiceprint Identification (VI). This method primarily involves five steps: feature extraction of Mel-Frequency Cepstral Coefficients, training of a universal background model (UBM), adaptive training of neutron/gamma Gaussian Mixture Model (GMM), model verification, and application. For 1000 small sample training sets provided by commercial organic scintillator detectors, the accuracy of this method was proven to be as high as 99 %, comparable to the classical charge integral method. The waveforms obtained under varying experimental conditions were used for unsupervised discrimination. The results demonstrate that this method offers high accuracy, robust feature extraction capabilities, strong generalization abilities, exceptional adaptability, and rapid computational speed.</div></div>","PeriodicalId":21055,"journal":{"name":"Radiation Measurements","volume":"187 ","pages":"Article 107483"},"PeriodicalIF":1.6,"publicationDate":"2025-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144297001","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}