Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment最新文献_第7页

Design and simulation of a beam shaping assembly for boron neutron capture therapy using a deuterium-deuterium compact neutron generator 用氘-氘紧凑型中子发生器进行硼中子俘获治疗的束形装置的设计与模拟

IF 1.4 3区物理与天体物理 Q3 INSTRUMENTS & INSTRUMENTATION

Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment

Pub Date : 2025-12-24 DOI: 10.1016/j.nima.2025.171257

Vahagn Ivanyan

This research presents the design and development of a Beam Shaping Assembly (BSA) optimized for a Deuterium-Deuterium (DD) Compact Neutron Generator (CNG)-based Boron Neutron Capture Therapy (BNCT) system. Monte Carlo simulations were conducted using the Geant4 toolkit, with design parameters aligned to the International Atomic Energy Agency (IAEA) recommendations for BNCT.

A comprehensive review of available DD CNGs capable of delivering high neutron yields was performed. Each component of the proposed BSA, including the choice of materials, geometries, and dimensions, is described in detail. An arrangement composed of up to five layers of different materials were optimized to enhance fast neutron moderation, reduce gamma dose, and filter thermal neutrons. The first layer evaluated natural molybdenum (nat-Mo), natural bismuth (nat-Bi), and natural tungsten (nat-W) to decrease the initial 2.5 MeV energy of the DD generated neutron flux. The second layer utilized thick iron, aluminum fluoride (AlF₃), ferrum aluminum fluoride, and aluminum for further moderation. Aluminum, ferrum aluminum fluoride, bismuth, and lithium fluoride were used in up to three additional layers for further moderation, thermal neutron filtration, and gamma-ray suppression.

The BSA was designed to produce an epithermal-to-thermal neutron flux ratio exceeding 20, as recommended by IAEA guidelines, while maintaining a 12 cm aperture radius and ensuring fast neutron and gamma-ray doses remain within safe limits for BNCT applications. The compact design enables integration into clinical environments with minimal modifications, supporting hospital-based BNCT adoption.

本研究提出了一种针对基于氘-氘（DD）紧凑型中子发生器（CNG）的硼中子捕获治疗（BNCT）系统进行优化的束整形组件（BSA）的设计和开发。使用Geant4工具包进行蒙特卡罗模拟，设计参数与国际原子能机构（IAEA）对BNCT的建议保持一致。对能够提供高中子产量的现有DD cng进行了全面审查。建议的BSA的每个组成部分，包括材料的选择，几何形状和尺寸，详细描述。一种由多达五层不同材料组成的排列被优化，以增强快中子的中化，减少伽马剂量，并过滤热中子。第一层评价了天然钼（nat-Mo）、天然铋（nat-Bi）和天然钨（nat-W）对降低DD产生的初始2.5 MeV中子通量的影响。第二层使用厚铁、氟化铝（AlF3）、氟化铝铁和进一步适度的铝。铝、铁、氟化铝、铋和氟化锂在多达三层的附加层中使用，以进一步缓和、热中子过滤和伽马射线抑制。按照原子能机构指导方针的建议，BSA的设计目标是产生超过20的热中子通量比，同时保持12厘米的孔径半径，并确保快中子和伽马射线剂量保持在BNCT应用的安全范围内。紧凑的设计能够以最小的修改集成到临床环境中，支持基于医院的BNCT采用。

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引用次数: 0

Commissioning and performance of IDATEN: A large fast-timing γ-ray detector array at the RIBF 在RIBF的IDATEN：一个大型快速定时γ射线探测器阵列的调试和性能

IF 1.4 3区物理与天体物理 Q3 INSTRUMENTS & INSTRUMENTATION

Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment

Pub Date : 2025-12-23 DOI: 10.1016/j.nima.2025.171239

B. Moon , J. Lee , Y. Jang , H. Watanabe , S. Nishimura , V. Phong , Q. Zeng , H. Baba , S. Bae , A.M. Bruce , H. Chen , S. Choi , A. Esmaylzadeh , J. Fischer , L.M. Fraile , N. Fukuda , G. Garcia De Lorenzo , S. Go , A. Görgen , M. Górska , M. Yoshimoto

A large fast-timing

γ

-ray detector array has been newly developed under the International Detector Assembly for fast-Timing measurements of Exotic Nuclei (IDATEN) project. The full IDATEN array comprises 82 LaBr₃(Ce)

γ

-ray detectors, of which 46 and 36 are provided by the KHALA and FATIMA collaborations, respectively. To assess the fast-timing performance of this large-scale system with stopped rare-isotope beams, a commissioning experiment was recently carried out at the Radioactive Isotope Beam Factory (RIBF) at RIKEN. Neutron-deficient rare isotopes near ¹⁰⁰Sn were produced via in-flight fragmentation of a ¹²⁴Xe primary beam. The fast-timing capability was evaluated using ⁹⁶Pd as the reference nucleus by measuring the half-lives of the

2_{1}^{+}

,

4_{1}^{+}

and

6_{1}^{+}

levels, which were populated through the decay of the long-lived

8_{1}^{+}

isomeric state. These results demonstrate the reliability of our experimental setup, including the readout electronics and data acquisition system, thereby validating its readiness for forthcoming physics experiments at the RIBF. Moreover, the measured half-life values are in agreement with previously reported literature values, with some determinations achieving improved precision.

在国际异核快速定时测量探测器组件（IDATEN）项目下，新研制了一种大型快速定时γ射线探测器阵列。完整的IDATEN阵列包括82个LaBr3(Ce) γ射线探测器，其中46个和36个分别由KHALA和FATIMA合作提供。为了评估这种具有停止稀有同位素束的大型系统的快速定时性能，最近在RIKEN的放射性同位素束工厂（RIBF）进行了调试实验。通过124Xe原束的飞行破碎产生了接近100Sn的缺中子稀有同位素。以96Pd为参考核，通过测量21+、41+和61+能级的半衰期来评估其快速定时能力，这些半衰期是通过长寿命的81+同分异构体衰变来填充的。这些结果证明了我们的实验装置的可靠性，包括读出电子和数据采集系统，从而验证了它为即将在RIBF进行的物理实验做好了准备。此外，测量的半衰期值与先前报道的文献值一致，其中一些测定的精度得到了提高。

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引用次数: 0

Trapezoidal Cherenkov radiator as an efficient calorimeter 梯形切伦科夫散热器作为一种高效的量热计

IF 1.4 3区物理与天体物理 Q3 INSTRUMENTS & INSTRUMENTATION

Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment

Pub Date : 2025-12-23 DOI: 10.1016/j.nima.2025.171247

A.A. Savchenko , S.B. Dabagov , A.A. Tishchenko

We report the results of Geant4 computer simulations of a calorimeter based on Cherenkov radiators of trapezoidal form. We study radiators made of lead glasses PbF₂ and SF2, and demonstrate a significant increase in their efficiency, up to 25 % compared with conventional rectangular radiators. Such calorimeters can be of use for upcoming muon experiments, and for improving the detection system for medical applications such as positron emission tomography.

本文报道了基于梯形切伦科夫辐射体的量热计的Geant4计算机模拟结果。我们研究了由铅玻璃PbF2和SF2制成的散热器，并证明了它们的效率显著提高，与传统的矩形散热器相比，效率提高了25%。这种量热计可以用于即将到来的μ子实验，并用于改进医学应用的检测系统，如正电子发射断层扫描。

引用次数: 0

Thermoelectric controller for diamond and silicon crystal X-ray optics active temperature management 热电控制器的金刚石和硅晶体x射线光学主动温度管理

IF 1.4 3区物理与天体物理 Q3 INSTRUMENTS & INSTRUMENTATION

Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment

Pub Date : 2025-12-23 DOI: 10.1016/j.nima.2025.171253

Ye Hong , Catherine C. Feng , Sophie Y. Liu , Brian Sun , Lindsey Yi , Shangjia Wang , Joseph Hu , Bo Yang , Juhao Wu

The remarkable brightness of X-ray Free Electron Lasers presents a formidable challenge in the form of high thermal power density. This intense heat can lead to substantial temperature increases, and therefore strain and deformation in the crystal X-ray optics responsible for manipulating and measuring X-rays. These thermomechanical effects can significantly compromise the quality of the experimental results. We demonstrated that there is promise in using Thermoelectric Cooler as an active temperature control method to reduce crystal strain and deformation, and therefore maintain the optical properties of the diamond and silicon X-ray optics device.

x射线自由电子激光器的超高亮度对其热功率密度提出了严峻的挑战。这种强烈的热量会导致温度大幅升高，从而导致负责操纵和测量x射线的晶体x射线光学元件的应变和变形。这些热机械效应会严重影响实验结果的质量。我们证明了热电冷却器作为一种主动温度控制方法有希望减少晶体应变和变形，从而保持金刚石和硅x射线光学器件的光学特性。

引用次数: 0

A magnetic mass spectrograph with large mass detection range for pulsed vacuum arc ion sources 一种具有大质量检测范围的脉冲真空电弧离子源磁质谱仪

IF 1.4 3区物理与天体物理 Q3 INSTRUMENTS & INSTRUMENTATION

Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment

Pub Date : 2025-12-22 DOI: 10.1016/j.nima.2025.171250

Jianlin Ke , Jinquan Zhang , Changgeng Zhou , Jingjing Zhang , Lixia Zhao , Mingbang Lv , Qianshun She , Wenjun Xie , Zhiguo Xu , Jingbin Shangguan , Jianjun Chang , Ruishi Mao , Hong Su , Jun Meng , Qinggao Yao , Hongbin Yan , Wei Zhang , Li An , Baili Liu , Jun Tang , Chunfeng Deng

A magnetic mass spectrograph has been developed for measuring the ion composition of pulsed vacuum arc ion sources at 60 kV extraction voltage. The mass spectrograph is comprised of an ion beam collimator, an einzel lens, a 114° dipole magnet, and a 416-channel Faraday-strip array detector. The main advantages of this mass spectrograph are its high simultaneous mass-to-charge ratio detection range and gapless Faraday-strip array detector. This paper introduces the design of the mass spectrograph and evaluates its performance in terms of resolving power and simultaneous detection range.

研制了一种磁质谱仪，用于测量60 kV提取电压下脉冲真空电弧离子源的离子组成。质谱仪由离子束准直器、埃因泽尔透镜、114°偶极磁铁和416通道法拉第带阵列探测器组成。该质谱仪的主要优点是具有较高的同时质荷比探测范围和无间隙法拉第带阵列探测器。本文介绍了该质谱仪的设计，并从分辨率和同时探测范围两方面对其性能进行了评价。

引用次数: 0

Monitoring 135Xe after the shutdown of a research reactor using gamma-ray spectroscopy 用伽马射线光谱学监测研究堆关闭后的135Xe

IF 1.4 3区物理与天体物理 Q3 INSTRUMENTS & INSTRUMENTATION

Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment

Pub Date : 2025-12-22 DOI: 10.1016/j.nima.2025.171252

Flynn Darby , Andrew Lucas , Michel Saliba , Sara Pozzi , Oskari Pakari

¹³⁵Xe, a high-yield fission product with a large neutron absorption cross section, can greatly influence the reactivity of a reactor, posing challenges to reactor operation and safety if the transient ¹³⁵ Xe concentration is not taken into account. To date, ¹³⁵Xe has only been monitored indirectly with neutron flux monitors, studied from off-gas, or studied in simulation. In this study, we show that ¹³⁵Xe in a zero-power research reactor can be directly monitored after shutdown, using gamma spectroscopy. We use an HPGe gamma-ray spectrometer in the beam port of the CROCUS research reactor and measure the ¹³⁵Xe and ¹³⁵I signature gamma-ray emissions (250 keV and 1260 keV, respectively) after shutting down the reactor. We directly measure the transient behavior of ¹³⁵Xe and ¹³⁵I, the commonly known “Xenon Pit” corresponding to maximum neutron absorption, following reactor shutdown. The expected ¹³⁵Xe peak time with known half-life values is 11.13 h, and we calculate 11.15 ± 0.22 h when fitting the measured data with free half-life parameters. We provide results for code validation, especially useful for reactor shutdown and accident scenarios, as well as reactivity margin predictors.

135Xe是一种高产量的裂变产物，具有较大的中子吸收截面，如果不考虑瞬态135Xe浓度，会对反应堆的反应性产生很大的影响，对反应堆的运行和安全构成挑战。迄今为止，135Xe仅通过中子通量监测器间接监测，从废气中进行研究，或在模拟中进行研究。在这项研究中，我们证明了零功率研究堆中的135Xe可以在关闭后使用伽马能谱直接监测。我们在CROCUS研究堆的束流口使用了HPGe伽马射线谱仪，在反应堆关闭后测量了135Xe和135I的特征伽马射线发射（分别为250 keV和1260 keV）。我们直接测量了135Xe和135I的瞬态行为，即通常所说的“氙坑”，对应于最大中子吸收，在反应堆关闭后。已知半衰期值的135Xe峰值时间为11.13 h，用自由半衰期参数拟合实测数据计算为11.15±0.22 h。我们提供了代码验证的结果，特别适用于反应堆关闭和事故场景，以及反应性裕度预测。

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引用次数: 0

Characterization of a neutron imaging facility based on a CCD camera and a LiF:ZnS(Cu) scintillator screen implemented around the Algerian Es-Salam nuclear research reactor 阿尔及利亚Es-Salam核研究堆采用CCD相机和LiF:ZnS（Cu）闪烁屏的中子成像设备

IF 1.4 3区物理与天体物理 Q3 INSTRUMENTS & INSTRUMENTATION

Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment

Pub Date : 2025-12-22 DOI: 10.1016/j.nima.2025.171249

Layachi Boukerdja , Omar Dendene , Mohamed Laid Yahiaoui , Maamar Touiza , Abdelkader Ali

In neutron imaging, the assessment of image quality is based on contrast level, the dynamic range, the signal-to-noise ratio and the spatial resolution limit, which in turn depend on several parameters such as collimation ratio (L/D), neutron beam intensity, effective gamma ray content, exposure time and image detector quality. The neutron imaging facility at the Algerian Es-salam nuclear research reactor is equipped with a slightly diverging collimator with a collimation ratio (L/D) of 215 and an image detector consisting of a 200 μm thick LiF:ZnS(Cu) scintillator coupled with a 16-bit cooled CCD camera. The facility will be dedicated to tomographic analysis for large objects based on light elements and certain metals depending on the facility's performance. In this work, the facility was characterized in terms of several parameters such as the minimum optimal exposure time, the effective gamma ray and effective backscattered radiation contents. The results obtained showed that the minimum optimal exposure time is 0.8 s, and by applying a new developed approach based on the use of the Beam Purity Indicator (BPI) of the ASTM E545 standard, the effective gamma rays and backscattered radiation contents were estimated to be 1.35 % and 9.86 % respectively. Moreover, the spatial resolution limit at high contrast of the facility was estimated to be 205 μm using Modulation Transfer Function (MTF) method.

在中子成像中，图像质量的评价基于对比度水平、动态范围、信噪比和空间分辨率极限，而这些又取决于准直比（L/D）、中子束强度、有效伽马射线含量、曝光时间和图像探测器质量等几个参数。阿尔及利亚Es-salam核研究堆的中子成像设施配备了一个准直比（L/D）为215的微发散准直器和一个由200 μm厚的LiF:ZnS（Cu）闪烁体和一个16位冷却CCD相机组成的图像探测器。根据设备的性能，该设备将专门用于基于轻元素和某些金属的大型物体的层析分析。在这项工作中，根据最小最佳暴露时间、有效伽马射线和有效背散射辐射含量等几个参数对该设施进行了表征。结果表明，最小最佳曝光时间为0.8 s，采用基于ASTM E545标准光束纯度指标（BPI）的新方法，估算出有效伽马射线和后向散射辐射含量分别为1.35%和9.86%。利用调制传递函数（Modulation Transfer Function， MTF）方法估计了高对比度下的空间分辨率极限为205 μm。

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引用次数: 0

Comparative study on conductive types of guard rings of silicon PIN detectors 硅PIN探测器保护环导电类型的比较研究

IF 1.4 3区物理与天体物理 Q3 INSTRUMENTS & INSTRUMENTATION

Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment

Pub Date : 2025-12-21 DOI: 10.1016/j.nima.2025.171246

Xiao Wang , Rui Jia , Yongyao Li , Mingpeng Zhang , Bingqian Yuan , Xiaoping Ouyang , Xing Li

Although p-type guard rings are commonly used in silicon PIN detectors, n-type guard rings, which have been less studied, also play a significant role in reducing leakage current and improving energy resolution. This study investigates the effect of different types of guard rings on the performance of Si PIN detectors. We designed and fabricated n-type guard ring PIN detectors alongside p-type guard ring PIN detectors, and tested their electrical properties and energy spectra. We also constructed TCAD simulations of both types of detectors with identical dimensions to corroborate the experiment, and used the experimental results to validate the simulation results. These efforts elucidate the operating principles of the n-type guard ring. The study reveals that the physical mechanisms of the n-type guard ring differ significantly from those of the p-type, enhancing its resistance to external disturbances and reducing leakage current, but it slightly lowers its energy resolution. Consequently, the n-type guard ring PIN exhibited lower leakage current and higher resistance to external interference than the p-type, with slightly lower energy resolution, yet still substantial. However, at the same time, the n-type guard ring exhibits limitations in effective detection area and increased power consumption, which cannot be ignored. Following the energy spectrum tests, the energy resolution of the p-type guard ring PIN was measured at 0.48%, while that of the n-type guard ring PIN was 0.74%, demonstrating that n-type guard rings can also achieve high performance. This study presents the structure-property relationship between the type of guard ring and detector performance in a more intuitive manner, providing new insights for selecting guard rings in detector design.

虽然p型保护环通常用于硅PIN探测器，但研究较少的n型保护环在降低泄漏电流和提高能量分辨率方面也具有重要作用。本文研究了不同类型的保护环对Si PIN探测器性能的影响。我们设计并制作了n型保护环PIN探测器和p型保护环PIN探测器，并测试了它们的电学性能和能谱。我们还构建了尺寸相同的两种探测器的TCAD仿真来验证实验结果，并用实验结果验证仿真结果。这些努力阐明了n型保护环的工作原理。研究表明，n型保护环的物理机制与p型保护环有明显不同，增强了保护环对外界干扰的抵抗力，降低了泄漏电流，但能量分辨率略有降低。因此，与p型相比，n型保护环PIN具有更低的泄漏电流和更高的抗外部干扰能力，能量分辨率略低，但仍然很可观。但与此同时，n型保护环在有效检测面积上存在局限性，功耗增加，这是不可忽视的。经过能谱测试，测得p型保护环PIN的能量分辨率为0.48%，n型保护环PIN的能量分辨率为0.74%，说明n型保护环也能达到较高的性能。本研究以更直观的方式呈现了保护环类型与探测器性能之间的结构-性能关系，为探测器设计中保护环的选择提供了新的见解。

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引用次数: 0

Optimizing a detection system for fissile material in nuclear disarmament verification 核裁军核查中裂变材料探测系统的优化

IF 1.4 3区物理与天体物理 Q3 INSTRUMENTS & INSTRUMENTATION

Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment

Pub Date : 2025-12-20 DOI: 10.1016/j.nima.2025.171237

Jihye Jeon , Rebecca S. Detwiler , Andrew J. Gilbert , Erik P. Gilson , Alexander Glaser , Robert J. Goldston , Christopher M. Jackson , Glen A. Warren

In arms control treaties, verification plays a crucial role in detecting non-compliance, deterring future violations, and building trust between state parties. Neutron interrogation that induces fission reactions in fissile isotopes and measures the resulting fission neutrons, could be employed for this purpose. This study aims to develop a system which can determine the presence of fissile material while intrinsically protecting information. In this paper, we focus on optimizing the system for discriminating between an enriched uranium block from a depleted uranium (DU) block. The system was built and we report on benchmark measurements with DU and 16% enriched uranium blocks. The Excalibur (Experiment for Calibration with Uranium) neutron source, a neutron spectrometer (redBubble Technology Industries (BTI) N-Probe), and superheated droplet detectors were used for these measurements. MCNP simulations provided insights into detector responses to fissile materials with varying isotopic compositions, confirming that the system functioned as designed.

在军备控制条约中，核查在发现不遵守情况、阻止未来的违规行为和在缔约国之间建立信任方面发挥着至关重要的作用。在可裂变同位素中诱导裂变反应并测量产生的裂变中子的中子探测仪可用于此目的。本研究旨在开发一种能够在本质上保护信息的同时确定裂变材料存在的系统。在本文中，我们的重点是优化系统来区分浓缩铀区块和贫化铀（DU）区块。建立了该系统，并报告了贫铀和16%浓缩铀块的基准测量结果。这些测量使用了Excalibur（铀校准实验）中子源、中子星光谱仪（redBubble Technology Industries (BTI) N-Probe）和过热液滴探测器。MCNP模拟提供了探测器对不同同位素组成的裂变材料的响应，证实了该系统的设计功能。

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引用次数: 0

Design and simulation of a coated confocal ellipsoidal capillary X-ray lens for laboratory X-ray source 实验室x射线源用涂层共焦椭球毛细x射线透镜的设计与仿真

IF 1.4 3区物理与天体物理 Q3 INSTRUMENTS & INSTRUMENTATION

Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment

Pub Date : 2025-12-19 DOI: 10.1016/j.nima.2025.171235

Yuchuan Zhong , Jingyue Hu , Mengfang Chen , Shangkun Shao , Xuepeng Sun , Tianxi Sun , Lu Hua

X-rays play a crucial role in advanced materials characterization, but efficiently manipulating highly divergent laboratory sources remains challenging. Conventional Ellipsoidal Monocapillary X-ray Lens (EMXL), typically fabricated from silicate glass tubes, suffer from limited acceptance angle, low source utilization, and weak focal intensity. Metal coatings such as Pt or Ir can extend the critical angle, but Coated EMXL (CEMXL) still provide limited intensity compression ratio due to their single-layer geometry. To overcome these limitations, researchers proposed a Confocal Nested Ellipsoidal Capillary Lens (CFEXL), which increases acceptance by coaxially nesting multiple capillaries. However, their simulations assumed an ideal uniform source and neglected realistic effects such as Gaussian source distribution, roughness, and figure errors. Here we design and numerically evaluate a Coated Confocal Ellipsoidal Capillary X-ray Lens (CCFEXL), combining Ir coating with a coaxial confocal geometry. A 3D ray-tracing model was developed to study its transmission and focusing performance under different conditions of incident X-ray energy, X-ray source size, roughness and figure error. Compared with uncoated EMXL, CFEXL and coated CEMXL, CCFEXL demonstrates higher transmission efficiency in the medium and high energy range, maintains a smaller and more stable focal spot, and achieves a higher intensity compression ratio. We also identify an optimal matching between source size and lens acceptance that maximizes intensity compression ratio. Roughness below ∼1 nm has negligible impact on its divergence, while figure errors above several hundred μrad degrade focal quality. These results provide a theoretical basis and structural guideline for building high performance laboratory X-ray focusing systems.

x射线在高级材料表征中起着至关重要的作用，但有效地操纵高度分散的实验室光源仍然具有挑战性。传统的椭球单毛细管x射线透镜（EMXL）通常由硅酸盐玻璃管制成，存在接收角度有限、光源利用率低、焦强度弱等问题。金属涂层（如Pt或Ir）可以延长临界角度，但涂层EMXL （CEMXL）由于其单层几何结构，仍然提供有限的强度压缩比。为了克服这些限制，研究人员提出了一种共聚焦嵌套椭球毛细血管透镜（CFEXL），它通过同轴嵌套多个毛细血管来增加接受度。然而，他们的模拟假设了一个理想的均匀源，而忽略了现实的影响，如高斯源分布、粗糙度和图形误差。本文设计了一种涂层共焦椭球毛细x射线透镜（CCFEXL），将红外涂层与同轴共焦几何结构相结合。建立了三维射线追踪模型，研究了不同入射x射线能量、x射线源尺寸、粗糙度和图形误差条件下的透射和聚焦性能。与未涂覆的EMXL、CFEXL和涂覆的CEMXL相比，CCFEXL在中高能范围内具有更高的传输效率，保持更小、更稳定的焦斑，实现更高的强度压缩比。我们还确定了光源尺寸和透镜接受度之间的最佳匹配，从而最大限度地提高了强度压缩比。小于1 nm的粗糙度对散度的影响可以忽略不计，而大于几百μrad的图像误差会降低焦质。这些结果为构建高性能实验室x射线聚焦系统提供了理论依据和结构指导。

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引用次数: 0