球形石墨空腔电离室壁修正因子模拟计算

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英文篇名：Monte-Carlo Simulation about Wall Correction Factor for the Spherical Graphite Cavity Chamber 作者：郝艳梅 ; 黄建微 ; 李德红 ; 王晨毅 ; 吴琦 英文作者：HAO Yan-mei;HUANG Jian-wei;LI De-hong;WANG Chen-yi;WU Qi;National Institute of Metrology;The University of South China; 关键词：计量学 ; 石墨空腔电离室 ; 壁修正因子 ; 蒙特卡罗模拟 英文关键词：metrology;;graphite cavity chamber;;wall correction factor;;Monte-Carlo simulation 中文刊名：JLXB 英文刊名：Acta Metrologica Sinica 机构：中国计量科学研究院;南华大学; 出版日期：2019-05-22 出版单位：计量学报 年：2019 期：v.40;No.180 基金：国家重点研发计划重点专项(2017YFF0206304) 语种：中文; 页：JLXB201903028 页数：4 CN：03 ISSN：11-1864/TB 分类号：172-175

摘要

采用蒙特卡罗方法对球形石墨空腔电离室壁修正因子K_(wall)进行模拟计算,开展光子能量、壁厚、石墨密度对K_(wall)的影响研究。计算结果显示对同一体积空腔电离室,K_(wall)随着能量的变化而发生变化,在低能区域K_(wall)值急剧减小; K_(wall)随壁厚增加近线性增加;同时,在模拟计算不确定度大于0. 2%时,石墨材料的密度对于K_(wall)的影响可以忽略。这些结果表明,对于石墨空腔电离室壁修正因子高精度的计算,需要考虑光子能量、壁厚以及石墨密度的影响。
        Calculate the wall correction factor K_(wall) of spherical graphite cavity chambers by MC( Monte Carlo)method,and study the influence of K_(wall) about photon energy,wall thickness and graphite density. And the result shows that for the same volume chambers K_(wall) sharply reduces with energy at the low energy side. As the wall thickness increases,K_(wall) approximates linearly increase. And when the calculation accuracy is greater than 0. 2 %,the effect of density can be neglected on the simulation of K_(wall) . The above results indicate that in order to calculate the wall correction factor of the graphite cavity chamber accurartely,photon energy,wall thickness and graphite density must be considered.

引文

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