高能质子照相中面密度的测量和不确定性分析  

Measurement of areal density and its uncertainty in high-energy proton radiography

作　　者：许海波[1] 

机构地区：[1]北京应用物理与计算数学研究所,北京100088

出　　处：《强激光与粒子束》2006年第3期477-482,共6页High Power Laser and Particle Beams

基　　金：国家自然科学基金委-中国工程物理研究院联合基金资助课题(10576006);中国工程物理研究院基金资助课题(20040654)

摘　　要：依据洛斯.阿拉莫斯国家实验室的质子照相概念,通过研究高能质子与物质的相互作用规律,给出了质子照相确定面密度的计算公式及其不确定性分析,阐述了质子照相鉴别材料组分的原理。相对于X光照相,质子通过面密度较大的物体后的通量明显增加,界面探测和密度重建更加准确。研究了多库仑散射和磁透镜系统的色散对质子照相空间分辨率的影响及解决途径。结果表明,高能质子照相在穿透能力、面密度测量、材料的组分识别、空间分辨率等方面都优于X光照相。According to proton radiography concepts of the Los Alamos National Laboratory, the expressions of areal density in high-energy proton radiography are obtained by studying the high-energy protons interactions with materials. The areal density uncertainty and the position resolution are analyzed. Compared with high-energy X-ray radiography, the detection of edges and density reconstruction for a thick object are more accurate as the transmitted flux of protons is increased. The effects of the multiple coulomb scattering and chromatic aberrations in the magnetic lenses on the spatial resolution are studied. It is shown that high-energy proton radiography is superior to high-energy X-ray radiography in penetrating power, areal density measurement, material composition identification and position resolution.

关 键 词：质子照相 面密度 库仑散射 平均自由程 角度准直器 

分 类 号：O434.1[机械工程—光学工程]