X射线能谱测量的蒙特卡罗成像模拟

王毅; 李勤; 李天涛

doi:doi:10.3788/hplpb20132511.3017

强激光与粒子束, 2013, 25 (11): 3017, 网络出版: 2013-11-14

X射线能谱测量的蒙特卡罗成像模拟

Monte Carlo imaging simulation for X-ray spectrum estimation

论文大纲

王毅 ^*李勤李天涛

作者单位

中国工程物理研究院流体物理研究所, 中国工程物理研究院脉冲功率科学与技术重点实验室, 四川绵阳 621900

X射线能谱蒙特卡罗方法成像模拟能谱重建 X-ray spectrum Monte Carlo method imaging simulation spectral reconstruction

摘要

针对高能强流电子束轰击高Z靶产生的X射线的能谱测量问题，采用蒙特卡罗方法进行成像模拟研究。高能X射线能谱通常由对X射线经过衰减体的直穿透射率曲线进行解谱获得。设计了带多准直孔的截锥体模型，在单次模拟成像中获得完整的衰减透射率曲线，有效避免了散射光子对透射率曲线以及X射线能谱重建的影响。成像面采用非均匀划分网格计数，将大部分探测计数点集中于各准直孔出口处，保证关注区域模拟成像的精细度，同时减少总体计算时间。

Abstract

Imaging simulation by means of the Monte Carlo method is performed for the spectrum reconstruction of the X-ray which is produced by high-energy intense-current electron beam striking a high-Z target. Generally, the high-energy X-ray spectrum can be resolved from the primary transmission curve when the X-ray passes through the attenuator. A truncated cone model with collimating apertures is designed, by which an entire attenuation transmission curve is obtained in a single imaging simulation. The scattering photons are effectively obstructed from disturbing the transmission curve and finally the spectrum reconstruction. A non-uniform grid for tallying is adopted for the imaging plane in order to concentrate most of the probing tallies at the exit of each collimating aperture, which guarantees a fine imaging for the concerned region while reduces the total computing time.

参考文献

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王毅, 李勤, 李天涛. X射线能谱测量的蒙特卡罗成像模拟[J]. 强激光与粒子束, 2013, 25(11): 3017. Wang Yi, Li Qin, Li Tiantao. Monte Carlo imaging simulation for X-ray spectrum estimation[J]. High Power Laser and Particle Beams, 2013, 25(11): 3017.

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