^(252)Cfα粒子的微剂量谱和径向剂量分布  

Microdosimetric spectra and radial dose distribution of ^(252)Cf α particles

作　　者：朱连芳[1] 李学宽[1] 陈学兵[1] 贺榆生[1] 朱少飞[1] 苏有武[1] 焦敦庞[1] 

机构地区：[1]中国科学院近代物理研究所,兰州730000

出　　处：《核技术》1998年第10期607-612,共6页Nuclear Techniques

基　　金：国家自然科学基金资助

摘　　要：用大容积(φ60mm×80mm)的圆柱型流气式组织等效正比计数器测定了^(252)Cfα粒子的微剂量谱和径向剂量分布.α粒子束在无窗的情况下直接穿入正比计数器发生能量沉积的机率R_b为1.测量结果证实:沿α粒子径迹由单次事件沉积的剂量平均比能z_(1D)(Gy)与距径迹核径向距离b(μm)之间符合z_(1D)=ab^(-x)的函数关系,当b<0.6482μm时,α=0.328,x=1.7;当b≥0.6482μm时,α=0.288, x=2.给出了求最大径向距离的方法.Microdosimetric spectra and radial dose distribution of 252 Cf a particles were measured by a large volume cylindrical flowing tissue-equivalent proportional counter(TEPC). Because a particles enter into the TEPC without a window, the probability of energy deposition per ion Rb is 1. The measured dose-mean specific energy z1D(Gy) from single-event varies with b' the radial distance from the track core, according to the formula z1D=ab-x. where a = 0.328 and x=1.7 when b<0.6482 μm. and a = 0.288 and x = 2 when 6≥0.6482μm. The method to determine the maximum radial distance (penumbra) is given.

关 键 词：正比计数器 微剂量谱 径向剂量分布 锎252 

分 类 号：O571.1[理学—粒子物理与原子核物理]