Radiation Measurements最新文献_第5页

RQR beam qualities measurement with the Timepix4 detector Timepix4探测器的RQR波束质量测量

IF 2.2 3区物理与天体物理 Q2 NUCLEAR SCIENCE & TECHNOLOGY

Radiation Measurements

Pub Date : 2025-11-28 DOI: 10.1016/j.radmeas.2025.107570

T. Genetay , L. Tlustos , M. Campbell , F. Bochud , P. Carbonez , J. Damet

This work presents, to the best of the authors’ knowledge, the first attempt at reconstructing X-ray spectra with a hybrid pixel detector for radiation protection applications in the scattered field around fluoroscopy devices. The performance of the Timepix4 detector was evaluated under reference conditions using RQR beam qualities. A dedicated methodology was developed to correct for detection efficiency, explicitly accounting for contributions from Compton scattering and the photoelectric effect. Accuracy was assessed through Monte Carlo simulations and comparisons with published RQR reference spectra. In addition, particle fluence measurements obtained with Timepix4 were validated against values derived from kerma factors and ionisation chamber measurements performed in a calibration laboratory. The results show excellent agreement between reconstructed and reference spectra up to

70 keV

, with residuals below 1.7% and relative photon fluence shifts within 5%. At higher energies, discrepancies increase due to the low detection efficiency of the silicon sensor, requiring large correction factors and leading to greater statistical fluctuations. Nevertheless, the system demonstrated acceptable performance up to

120 keV

, with fluence shifts remaining below 16%. Linearity was confirmed across all beam qualities and intensities investigated, consistent with previous studies on earlier Timepix ASIC generations. Overall, these findings demonstrate that Timepix4 can provide reliable spectral and fluence measurements in reference X-ray beams, offering valuable information for radiation protection studies in scattered fields where conventional detectors are of limited use. Future improvements in readout bandwidth and spectral deconvolution methods are expected to extend its applicability to higher energies and clinical environments.

据作者所知，这项工作首次尝试用混合像素探测器重建x射线光谱，用于透视装置周围散射场的辐射防护应用。在参考条件下，利用RQR波束质量评价Timepix4探测器的性能。开发了一种专门的方法来纠正检测效率，明确地考虑了康普顿散射和光电效应的贡献。通过蒙特卡罗模拟和与已发表的RQR参考光谱的比较来评估准确性。此外，用Timepix4获得的粒子通量测量值与在校准实验室进行的kerma因子和电离室测量得出的值进行了验证。结果表明，在70keV范围内，重建光谱与参考光谱具有良好的一致性，残差在1.7%以下，相对光子通量漂移在5%以内。在较高的能量下，由于硅传感器的检测效率较低，差异增大，需要较大的校正因子，导致更大的统计波动。尽管如此，该系统在高达120keV的电压下表现出了可接受的性能，影响位移保持在16%以下。所有被调查的光束质量和强度都证实了线性，这与之前对Timepix ASIC的早期研究一致。总的来说，这些发现表明Timepix4可以在参考x射线光束中提供可靠的光谱和通量测量，为传统探测器用途有限的散射场辐射防护研究提供有价值的信息。未来在读出带宽和频谱反卷积方法方面的改进有望将其应用于更高能量和临床环境。

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引用次数: 0

Development of a high-speed and precise automatic reading system of CR-39 plastic nuclear track detector for neutron dose measurements CR-39型塑料核径迹探测器高速精密自动读数系统的研制

IF 2.2 3区物理与天体物理 Q2 NUCLEAR SCIENCE & TECHNOLOGY

Radiation Measurements

Pub Date : 2025-11-28 DOI: 10.1016/j.radmeas.2025.107572

Takuya Hashizume, Ryuji Akino, Hiroshi Sekiguchi, Chizuru Ojima, Yumi Kanie, Masami Sonda, Hiroki Hakamata, Akifumi Suzuki, Mitsuo Tsubomatsu, So Kitazawa, Yuki Oda

The well-known CR-39, or poly allyl diglycol carbonate (PADC), has been widely used for personal neutron dosimetry for over 40 years. For providers of individual monitoring service (IMS) of neutron dose, it is necessary to establish an automatic reading system for CR-39 detectors in two aspects: to quickly measure a large number of detectors returned from users, and to ensure precision and accuracy that meet the requirements of the ISO/IEC 17025 standard. In this study, a novel high-speed and precise system composed of three parts was developed: (I) image acquisition of etched tracks on CR-39 detectors using an optical microscope with an autofocusing module and a high-speed scanning stage, (II) image processing of the tracks using an integrated software for automatic pit-counting on CR-39 (ISAP-39), including dedicated image processing in two steps, judging exposure in screening mode and evaluating neutron dose in precise reading mode, and (III) data reviewing by dosimetry experts. In the performance evaluation of the system, the following results were confirmed: high-speed scanning with 30 s per detector, high image-processing performance with 0 % false positive detection rate for neutron-induced tracks in screening and over 83 % true positive rate in precise reading, capability to describe differences in track features due to different neutron sources, and capability for precise dose measurements, including coefficient of variation, linearity, and track counting uncertainties. Moreover, in the operational study, the system was confirmed to be valid in terms of the screening function, threshold setting, pass rate stability in screening, and validity of precise reading and data reviewing. Consequently, the CR-39 reading system was proven to have sufficient performance in terms of reading speed and measurement precision.

众所周知的CR-39，或聚烯丙基碳酸二甘醇（PADC），已被广泛用于个人中子剂量测定超过40年。对于中子剂量个体监测服务（IMS）提供商来说，建立CR-39探测器自动读数系统的必要性体现在两个方面：一是快速测量大量用户返回的探测器，二是确保精确度和准确度满足ISO/IEC 17025标准的要求。本研究开发了一种由三部分组成的新型高速精密系统：(1)利用带自动对焦模块和高速扫描级的光学显微镜对CR-39探测器上蚀刻轨迹进行图像采集；(2)利用CR-39自动坑计数集成软件（ISAP-39）对轨迹进行图像处理，包括两步专用图像处理，筛选模式下的曝光判断和精确读取模式下的中子剂量评估；(3)剂量学专家对数据进行审查。在系统的性能评价中，确认了以下结果：高速扫描，每个探测器30秒，高图像处理性能，在筛选中对中子诱导轨迹的假阳性检出率为0%，在精确读数中真阳性率超过83%，能够描述由于不同中子源导致的轨迹特征差异，以及精确剂量测量的能力，包括变异系数，线性度和轨迹计数不确定性。在运行研究中，从筛选功能、阈值设置、筛选通过率稳定性、精准读取和数据审核的有效性等方面验证了系统的有效性。因此，CR-39读数系统在读取速度和测量精度方面具有足够的性能。

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引用次数: 0

On the correction of lateral response artifact in accelerated radiochromic film dosimetry protocols 加速放射色膜剂量测定方案中侧向响应伪影的校正

IF 2.2 3区物理与天体物理 Q2 NUCLEAR SCIENCE & TECHNOLOGY

Radiation Measurements

Pub Date : 2025-11-26 DOI: 10.1016/j.radmeas.2025.107571

S. Panzuela , A.M. Bruque , J. Macías

This study investigates the correction of the lateral response artifact (LRA) in accelerated protocols for radiochromic film dosimetry that shorten the time between irradiation and read-out. In these protocols, the LRA is assessed by pixel profiles along the longest axis of radiochromic film strips that are scanned parallel to the axis of artifact. The interplay between the non-uniform response of flatbed scanners and unavoidable heterogeneities in the radiation fields of linear accelerators modifies these pixel profiles, deviating them from their real behavior. This phenomenon has a negative impact on radiochromic film dosimetry. To solve this issue, first-order variations in the homogeneity of the radiation fields were subtracted from the pixel profiles. We studied dose distributions of 30 × 30 cm² square fields at different dose levels and realistic radiotherapy treatment plans, using 6 MV and 6 MV flattening filter free energies. The radiochromic film models utilized were EBT4 and EBT-XD. For evaluation, gamma analysis (2 %,2 mm) and relative root mean square error metrics were employed. Comparisons against reference measurements demonstrate this novel correction is highly effective in suppressing radiation field heterogeneities, leading to enhanced dosimetric accuracy. Moreover, this study presents a semi-analytical expression for the LRA correction, which contributes to reducing uncertainties.

本研究探讨了在加速方案中的横向响应伪影（LRA）的校正，以缩短辐照和读出之间的时间。在这些方案中，LRA是通过沿平行于伪影轴扫描的放射变色薄膜条的最长轴的像素轮廓来评估的。平板扫描仪的非均匀响应与线性加速器辐射场中不可避免的异质性之间的相互作用改变了这些像素轮廓，偏离了它们的真实行为。这种现象对放射线致色膜剂量学有不利影响。为了解决这一问题，从像素轮廓中减去辐射场均匀性的一阶变化。利用6 MV和6 MV压平滤波自由能，研究了不同剂量水平下30 × 30 cm2方形场的剂量分布和现实放疗方案。使用的放射变色膜模型为EBT4和EBT-XD。为了评估，采用伽玛分析（2%,2mm）和相对均方根误差指标。与参考测量值的比较表明，这种新的校正在抑制辐射场非均质性方面非常有效，从而提高了剂量学精度。此外，本研究提出了LRA修正的半解析表达式，有助于减少不确定性。

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引用次数: 0

Physical model construction and experimental verification of measuring Rn-222 concentration in water by spray method 喷雾法测量水中钌-222浓度的物理模型构建及实验验证

IF 2.2 3区物理与天体物理 Q2 NUCLEAR SCIENCE & TECHNOLOGY

Radiation Measurements

Pub Date : 2025-11-26 DOI: 10.1016/j.radmeas.2025.107573

Shicheng Luo, Zhongkai Fan, Ruomei Xie, Xinyue Yang, Xianfa Mao, Chenxi Zu, Feng Xiao, Hongbo Xu, Yi Liu, Hao You, Haoyu You, Jia Liu, Cheng Luo, Hongzhi Yuan, Yanliang Tan

Rn-222 in water is not only a potential threat to human health, but also an important tracer for studying groundwater flow and crustal fracture system. The physical model of the existing method for measuring Rn-222 in water by the spray technique has not been made public. In this paper, a mathematical model for measuring Rn-222 concentration in water by spray method is established. A small spray device is designed and combined with RAD7 radon monitor to form a field measurement system for Rn-222 concentration in water. Six groups of field experiments were carried out in different locations around Yixin Lake in Hengyang Normal University, Hunan Province to verify the effectiveness of the model. The results show that the determination coefficient (R²) of the model is higher than 0.87, and the conversion efficiency of Rn-222 from water phase to gas phase is higher than 77 %, and the conversion efficiency is within two standard deviations. At the same time, the influence of leakage on the measurement results is analyzed. When the leakage rate exceeds 1

\times

10⁻⁴ s⁻¹, the measured Rn-222 concentration in water will be underestimated by about 20 %. The sensitivity of this measurement system is 0.0012 CPM/(Bq/m³). At a water temperature of 34.1 °C, the detection concentration range is from 0.7 to 133,689 Bq/m³.This study provides theoretical basis and technical support for rapid and accurate in-situ measurement of Rn-222 in natural water.

水中的钌-222不仅是对人类健康的潜在威胁，而且是研究地下水流动和地壳断裂系统的重要示踪剂。现有的喷雾法测定水中钌-222的物理模型尚未公开。本文建立了喷雾法测定水中钌-222浓度的数学模型。设计了一种小型喷雾装置，并与RAD7型氡监测仪相结合，组成了水中氡浓度的现场测量系统。在湖南衡阳师范学院宜新湖周边不同地点进行了6组野外试验，验证了该模型的有效性。结果表明，该模型的决定系数（R2）大于0.87，Rn-222从水相到气相的转化效率大于77%，转化效率在2个标准差范围内。同时，分析了泄漏对测量结果的影响。当泄漏速率超过1 × 10−4 s−1时，测得的水中铼-222浓度将被低估约20%。该测量系统的灵敏度为0.0012 CPM/(Bq/m3)。水温为34.1℃时，检测浓度范围为0.7 ~ 133,689 Bq/m3。本研究为快速准确地原位测定天然水中钌-222含量提供了理论依据和技术支持。

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引用次数: 0

Offsetting circularity within an extended quartz luminescence defect pair model 扩展石英发光缺陷对模型中的偏移圆度

IF 2.2 3区物理与天体物理 Q2 NUCLEAR SCIENCE & TECHNOLOGY

Radiation Measurements

Pub Date : 2025-11-22 DOI: 10.1016/j.radmeas.2025.107567

Owen M. Williams, Nigel A. Spooner

We critically examine the quartz defect pair model, within which physical explanations of quartz thermoluminescence and optically stimulated luminescence (OSL) were introduced. We address the apparent circularity of the model, in that it appears to lack an appropriate OSL terminal reaction. In particular, by appropriately analysing prior spectral OSL measurements, we demonstrate that the prominent primary peak centred at 365 nm is accompanied by a smaller secondary peak. With this insight, we proceed to extend the existing defect pair model by introducing a new OSL reaction pair which not only takes account of the secondary peak but also offsets the source of the circularity. We complete our study by introducing a configurational coordinate diagram that includes a new terminating antibonding state, the presence of which is consistent with both the measurement data and our defect pair model extension.

我们严格检查石英缺陷对模型，其中石英热释光和光激发发光（OSL）的物理解释引入。我们解决了模型的明显循环性，因为它似乎缺乏适当的OSL末端反应。特别是，通过适当分析先前的光谱OSL测量，我们证明了以365 nm为中心的突出的主峰伴随着一个较小的次峰。有了这一认识，我们通过引入一个新的OSL反应对来扩展现有的缺陷对模型，该反应对不仅考虑了二次峰，而且还抵消了圆的来源。我们通过引入一个包含新的终止反键态的构型坐标图来完成我们的研究，它的存在与测量数据和我们的缺陷对模型扩展是一致的。

引用次数: 0

Electron spin resonance spectroscopy and Monte Carlo simulation for fossils age determination from new historical park in Thailand 电子自旋共振光谱和蒙特卡罗模拟用于泰国新历史公园化石年龄测定

IF 2.2 3区物理与天体物理 Q2 NUCLEAR SCIENCE & TECHNOLOGY

Radiation Measurements

Pub Date : 2025-11-22 DOI: 10.1016/j.radmeas.2025.107569

Sirikorn Pongtornkulpanich , Patcharin Naemchanthara , Weeranut Kaewwiset , Sumalee Ninlaphruk , Pichet Limsuwan , Kittisakchai Naemchanthara

Ban Phot Historical Park in Phetchabun province is a new historical park in Thailand. However, the fossil remains in this historical park have been reported by taxonomic identification to be originating from the Carboniferous–Permian period. Confirming the age of these remains using electron spin resonance (ESR) spectroscopy coupled with neutron activation analysis is necessary. Sedimentary rocks from Ban Phot Historical Park were separated into fossil shells and soils. Taxonomic identification indicated that the overall morphologies corresponded to a brachiopod, specifically Orthotichia javanapheti and Marginifera banphotensis. The chemical composition and crystal structure of the fossil shells were examined by X-ray fluorescence spectroscopy and X-ray diffractometry, respectively, revealing high silicon content and a quartz phase. All fossil shells were applied irradiation doses ranging from 0 to 15 kGy. Free radicals were measured by ESR spectroscopy to quantify the accumulated dose (AD). The results demonstrated that the free radicals comprised CO₂⁻ species derived from carbonate. The AD varied from 9298.6 ± 186.0 Gy to 9516.1 ± 190.3 Gy. Neutron activation analysis determined the concentrations of ²³⁸U, ²³²Th, and ⁴⁰K in shells and soils for annual dose-rate (D) estimation. Thereafter, AD from ESR dating was combined with a Monte Carlo simulation to estimate fossil age. The ages obtained by ESR agreed with those derived via the Monte Carlo simulation using the DATA program, aligning with the Carboniferous period. Moreover, this age appears credible and may fill a gap in geological studies of the new historical park at Ban Phot, Phetchabun province.

位于碧差汶省的班普历史公园是泰国一个新的历史公园。然而，在这个历史公园里的化石已经被分类鉴定为来自石炭-二叠纪时期。利用电子自旋共振（ESR）光谱结合中子活化分析来确定这些遗骸的年龄是必要的。Ban Phot历史公园的沉积岩被分离成化石壳和土壤。分类学鉴定表明其总体形态属于腕足动物，特别是爪哇正鱼和banphotensis边缘鱼。通过x射线荧光光谱和x射线衍射对化石壳的化学成分和晶体结构进行了检测，发现化石壳具有高硅含量和石英相。所有化石壳都受到0至15千戈瑞的辐照剂量。ESR光谱法测定自由基，定量累积剂量（AD）。结果表明，自由基由来源于碳酸盐的CO2−组成。AD变化范围为9298.6±186.0 Gy ~ 9516.1±190.3 Gy。中子活化分析测定了壳和土壤中238U、232Th和40K的浓度，用于估算年剂量率(D)。此后，从ESR测年得到的AD与蒙特卡罗模拟相结合来估计化石的年龄。ESR计算得到的年龄与DATA程序Monte Carlo模拟得到的年龄一致，与石炭纪一致。此外，这个年龄似乎是可信的，并可能填补在phchabun省Ban Phot的新历史公园的地质研究的空白。

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引用次数: 0

Highly variable light attenuation across a gneiss rock wall in eastern Greenland 格陵兰岛东部片麻岩岩壁上高度可变的光衰减

IF 2.2 3区物理与天体物理 Q2 NUCLEAR SCIENCE & TECHNOLOGY

Radiation Measurements

Pub Date : 2025-11-20 DOI: 10.1016/j.radmeas.2025.107568

Rachel K. Smedley , Mae Fletcher , Alex Honnold , Aldo Kane , Heidi Sevestre

Exposure ages and erosion rates determined using rock surface luminescence have the potential to revolutionalise Quaternary Science. However, accurately quantifying μ (the light attenuation coefficient) is a significant challenge. Our study shows how variable light attenuation properties (i.e. μ) can be for five samples taken from a small (423 m) elevation range of a near-vertical gneiss rock wall, which we would have expected to have had a shared μ value. The light attenuation properties varied on multiple scales: (i) between samples; (ii) between replicate cores; and (iii) between slices within a core. To avoid the between sample variability, we need to either measure μ directly from the rock cores used to derive the exposure age or erosion rate, or prove that these samples and the sample used to calibrate μ have identical light attenuation properties. To avoid variability between replicate cores observed in samples, it may be more accurate to derive exposure ages or erosion rates using a single core with identical light attenuation properties to the sample used to calibrate μ. Finally, where possible, we should avoid rocks that have hetergeneous mixes of minerals with different opacities (lighter and darker). However, if it is not possible, we should routinely measure red-green-blue (RGB) values to link the presence of any low datapoints in the luminescence depth profiles to overlying lighter-coloured minerals that could have caused light ‘piping’. Our findings further emphasise the detailed consideration required for deriving μ to determine accurate exposure ages and erosion rates.

利用岩石表面发光确定的暴露年龄和侵蚀速率有可能彻底改变第四纪科学。然而，精确地量化μ（光衰减系数）是一个重大挑战。我们的研究表明，从一个接近垂直的片麻岩岩壁的小海拔范围（423米）中采集的五个样品的光衰减特性（即μ）是如何变化的，我们本以为它们具有共同的μ值。光衰减特性在多个尺度上存在差异：(1)样品间；（ii）在复制核心之间；（iii）在一个核心内部的切片之间。为了避免样品之间的差异，我们需要直接从岩石岩心中测量μ，以获得暴露年龄或侵蚀速率，或者证明这些样品与用于校准μ的样品具有相同的光衰减特性。为了避免样品中观察到的重复岩心之间的差异，使用与用于校准μ的样品具有相同光衰减特性的单个岩心来计算暴露年龄或侵蚀速率可能更准确。最后，在可能的情况下，我们应该避免含有不同不透明度（浅色和深色）的矿物的异质混合物的岩石。然而，如果不可能，我们应该定期测量红绿蓝（RGB）值，以将发光深度剖面中任何低数据点的存在与可能导致光“管道”的上覆浅色矿物联系起来。我们的发现进一步强调了为确定准确的暴露年龄和侵蚀速率而推导μ所需的详细考虑。

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引用次数: 0

The development of a DNN-assisted track analysis system for CR-39-based space radiation dosimetry 基于cr -39的空间辐射剂量测定中dnn辅助航迹分析系统的研制

IF 2.2 3区物理与天体物理 Q2 NUCLEAR SCIENCE & TECHNOLOGY

Radiation Measurements

Pub Date : 2025-11-19 DOI: 10.1016/j.radmeas.2025.107565

Jun Hu, Satoshi Kodaira

CR-39 plastic nuclear track detectors are widely used in space radiation dosimetry due to their high sensitivity to charged particles and ability to record linear energy transfer (LET) information. Conventional CR-39 analysis tools can rapidly detect particle tracks in general dosimetry, however, they are not tailored for space radiation applications that require classification of valid tracks and extraction of morphology parameters to estimate LET, motivating the use of an automated approach. In this study, we propose a Deep Neural Network (DNN)-assisted track analysis system based on the Mask Region-based Convolutional Neural Network (R-CNN) framework to automate the detection and segmentation of particle tracks in CR-39 detectors.

The model was trained using a transfer learning strategy with weights pretrained on the MS COCO dataset and fine-tuned on annotated CR-39 images. It achieved mean average precision (mAP) values of 81.5 % for detection and 81.4 % for segmentation. The system demonstrated robust performance in handling overlapping tracks and significantly improved analysis efficiency, reducing the processing time for a typical sample from several hours to approximately 2 min.

A comparative analysis with conventional methods showed strong agreement in track counts and absorbed dose estimates, with an average difference of 4.7 % in valid track numbers and 11.2 % in absorbed dose. The discrepancy in dose estimation was primarily attributed to differences in ellipse fitting methods used for LET calculations. Despite challenges in classifying small or low-contrast tracks, the proposed DNN-assisted method offers a promising solution for high-throughput, reliable, and standardized CR-39 track analysis in space radiation dosimetry.

CR-39塑料核径迹探测器因其对带电粒子的高灵敏度和记录线性能量传递（LET）信息的能力而广泛应用于空间辐射剂量测定。传统的CR-39分析工具可以在一般剂量学中快速检测粒子轨迹，然而，它们并不适合空间辐射应用，因为空间辐射应用需要对有效轨迹进行分类和提取形态参数来估计LET，因此需要使用自动化方法。在这项研究中，我们提出了一种基于基于掩模区域的卷积神经网络（R-CNN）框架的深度神经网络（DNN）辅助轨迹分析系统，以实现CR-39探测器中粒子轨迹的自动检测和分割。该模型使用迁移学习策略进行训练，该策略在MS COCO数据集上预训练了权重，并在带注释的CR-39图像上进行了微调。平均检测精度（mAP）为81.5%，分割精度为81.4%。该系统在处理重叠轨迹方面表现出强大的性能，并显着提高了分析效率，将典型样品的处理时间从几个小时减少到大约2分钟。与传统方法的比较分析表明，迹线计数和吸收剂量估计非常一致，有效迹线数平均相差4.7%，吸收剂量平均相差11.2%。剂量估计的差异主要归因于用于LET计算的椭圆拟合方法的差异。尽管在分类小径迹或低对比度径迹方面存在挑战，但所提出的dnn辅助方法为空间辐射剂量学中高通量、可靠和标准化的CR-39径迹分析提供了一个有希望的解决方案。

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引用次数: 0

Advanced Monte Carlo simulation as a practical solution for mixed-field dosimetry 先进的蒙特卡罗模拟作为混合场剂量测定的实用解决方案

IF 2.2 3区物理与天体物理 Q2 NUCLEAR SCIENCE & TECHNOLOGY

Radiation Measurements

Pub Date : 2025-11-11 DOI: 10.1016/j.radmeas.2025.107556

Junyoung Lee , Sangmin Lee , Jongyul Kim , Jinhwan Kim , Byung-gun Park , Young Soo Han , Jeonghun Oh , Sung-Joon Ye

This work aims to perform a comprehensive characterization of the mixed neutron and photon fields at the Ex-core Neutron Facility (ENF) of the HANARO reactor by complementing Monte Carlo (MC) simulations with selected experiments. A full-scope MCNP 6.3 model of the reactor–beamline system, augmented with NJOY + NCrystal coherent-elastic libraries for silicon and bismuth, was used to transport neutrons from core to beam port. Activation-induced γ-rays were evaluated by coupling the resulting particle phase-space data at the beam port with PHITS/DCHAIN. Westcott fluence rate, the thermal neutron fluence standardized to a 2200 m/s reference under 1/v cross-sectional assumption, and photon dose were measured at 20 MW_th condition using a cadmium-shielded 6 × 6 LiF TLD-100/TLD-700 array and gold-foil activation; statistical and systematic uncertainties were propagated. The calculated Westcott fluence rate agreed with TLD and gold activation benchmarks within their combined uncertainties. Incorporation of Bragg scattering effects increased the predicted thermal-neutron fluence rate at the port by about 150 %, suggesting the significance of crystal effects in beam filters. TLD Type A uncertainty was halved through the use of elemental-correction coefficients. Remaining differences in photon dose were predominantly attributed to short-lived γ-rays from cadmium activation, which were effectively simulated by the coupled MCNP–PHITS method. These results show that well-validated MC simulations can supply detailed energy, angular, and spatial data in situations where it is not practical to make direct measurements, providing a robust and cost-effective basis for mixed-field dosimetry and related neutron-beam applications.

本研究旨在通过蒙特卡罗（MC）模拟和选定的实验，对HANARO反应堆前核中子设施（ENF）的混合中子和光子场进行全面表征。采用全尺寸MCNP 6.3型反应堆-束线系统模型，增强了用于硅和铋的NJOY + NCrystal相干弹性库，用于将中子从堆芯传输到束口。利用PHITS/DCHAIN耦合得到的粒子相空间数据，对激活诱导的γ射线进行了评价。利用6 × 6 LiF TLD-100/TLD-700阵列和金箔活化，在20 mw条件下测量了Westcott通量，即在1/v截面假设下标准化到2200 m/s的热中子通量；统计和系统的不确定性被传播。计算的Westcott影响率与TLD和黄金活化基准在其综合不确定性范围内一致。Bragg散射效应的加入使端口处的热中子通量预测率提高了约150%，这表明晶体效应在光束滤光器中的重要性。通过使用元素校正系数，TLD A型不确定度减半。剩余的光子剂量差异主要归因于镉活化产生的短寿命γ射线，通过耦合MCNP-PHITS方法有效地模拟了这一差异。这些结果表明，在无法进行直接测量的情况下，经过良好验证的MC模拟可以提供详细的能量、角度和空间数据，为混合场剂量学和相关中子束应用提供了可靠和经济的基础。

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引用次数: 0

Corrigendum to “Absorbed doses in bricks and TL-dosimeters due to anthropogenic and natural environmental radiation sources” [Radiat. Meas. 140 (2021) 106458] 人为和自然环境辐射源在砖和tl剂量计中的吸收剂量的勘误表[辐射]。平均数。140 (2021)106458]

IF 2.2 3区物理与天体物理 Q2 NUCLEAR SCIENCE & TECHNOLOGY

Radiation Measurements

Pub Date : 2025-11-11 DOI: 10.1016/j.radmeas.2025.107555

Alexander Ulanowski , Mauritius Hiller , Clemens Woda

引用次数: 0