小型γ相机压缩效应的研究  

Monte Carlo Study on Image Shrinkage of a Small Gamma Camera

作　　者：曾海宁[1] 许咨宗[1] 汪兆民[1] 李澄[1] 王丛蓉 

机构地区：[1]中国科学技术大学近代物理系,合肥230026

出　　处：《高能物理与核物理》2000年第2期166-171,共6页High Energy Physics and Nuclear Physics

基　　金：国家自然科学基金资助项目!( 197750 54 )&&

摘　　要：通过Monte -Carlo模拟 ,研究了小型单晶体γ相机中晶体的几何尺寸、表面光学条件及出射玻璃窗的几何尺寸对压缩效应的影响 。Based on the interaction of γ ray with NaI(Tl) crystal and the transportation of luminescence photons produced in the crystal, a simulation model has been setup using the GEANT3 codes for a small Gamma Camera with a planar NaI(Tl) crystal coupled to a position sensitive photomultiplier (Hamamatsu R2486-05). The results demonstrate that the image is significantly shrunk from the circumference to the center because of the asymmetry of the spacial distribution of the photoelectrons. The quantity of shrinkage depends on the thickness of both the crystal and glass window. Treatment of the edge surface of the crystal is very sensitive to the shrinkage of image. Suggestions for suppressing the image shrinkage are presented.

关 键 词：小型γ相机 压缩效应 光电子空间分布 蒙特卡罗模拟 单晶体 闪烁光子 PSPMT 玻璃窗厚度 探测器 

分 类 号：TB852[一般工业技术—摄影技术]