多探头全身计数器探测效率随体模大小的变化及修正

VARIATION OF DETECTION EFFICIENCY OF A FIXED 4 DETECTOR WHOLE BODY COUNTER WITH THE DIMENSION OF PHANTOM

本文介绍利用计算机对全身计数器进行效率刻度的方法。文中计算了一个固定多探头全身计数器系统对不同大小体模的探测效率，分析了探测效率随体模长度和体厚因子变化的关系，并给出了对于１３７Ｃｓ源，通过修正参考人体模的探测效率而得到不同大小（身长１４５～１８５ｃｍ，体重４５～８７ｋｇ）体模探测效率的近似公式。

The detection efficiency of a fixed 4 detector whole body counter to a series of phantoms (with different dimension) were calculated by computer program. The variation of detection efficiency with the lenghth and body build index the phantom were analysed. For 137 Cs, as an example, an approximate method is presented to calculate the detection efficiency of phantoms with various dimensions (lenghth: 145～185 cm, weight: 45～87 kg) by adjusting the detection efficiency of reference men phantom.