摘要
用数值模拟的方法研究了FTO客体材料的线吸收系数随着穿透材料深度的变化关系,并拟合出材料有效线吸收系数与厚度之间的函数表达式。研究结果表明,在闪光照相中X光能谱发生了硬化,并随着穿透材料深度的增加谱平均线吸收系数会随之减小。FTO客体中钨的平均有效线吸收系数0.838(4.53%)cm-1,铜的平均有效线吸收系数0.297(4.96%)cm-1,能谱效应对有效线吸收系数的影响小于5%。在图像重建中利用上述的线吸收系数能够反演出精度达5%的材料密度。
The relation between the line attenuation coefficient and the material thickness of FTO has been studied, and the function between them has been given. The results show that the efficient linear attenuation coefficient decreases when the thickness of material increases in the transmission direction of X-ray. Specially,the average efficient attenuation coefficient in the FTO is 0.838cm^(-1) for tungsten with precision of 4.5% and 0.297cm^(-1) for copper with precision of 5.0%. The spectrum effect on attenuation coefficient is less than 5%. The material densities can be reconstructed with such precision.
出处
《强激光与粒子束》
EI
CAS
CSCD
北大核心
2004年第10期1356-1360,共5页
High Power Laser and Particle Beams
基金
国防科技基础研究基金资助课题
关键词
闪光照相
有效线吸收系数
谱硬化
解析法
Radiography
Efficient linear attenuation coefficient
Spectrum hardening
Analytical method
