单球中子谱仪的能量响应模拟及解谱方法研究

辐射防护 ›› 2019, Vol. 39 ›› Issue (4): 280-286.

单球中子谱仪的能量响应模拟及解谱方法研究

邹益晟¹, 肖德涛¹, 张伟华², 王志强², 刘毅娜², 李春娟²

1.南华大学核科学技术学院,湖南衡阳 421000;
2.中国原子能科学研究院计量测试部,北京 102413

收稿日期:2018-08-29 出版日期:2019-07-15 发布日期:2019-10-29
通讯作者: 肖德涛。E-mail:13307478601@189.cn
作者简介:邹益晟(1994—),男,2012年本科毕业于南华大学核科学技术学院核工程与核技术专业,现为南华大学核科学技术学院辐射防护与环境保护专业在读研究生。E-mail:zouyisheng_94@qq.com

Energy response simulation and unfolding method research ofsingle sphere neutron spectrometer

ZOU Yisheng¹, XIAO Detao¹, ZHANG Weihua², WANG Zhiqiang², LIU Yina², LI Chunjuan²

1.School of Nuclear Science and Technology,University of South China,Hunan Hengyang 421001;
2. Division of Radiation Metrology,China Institute of Atomic Energy,Beijing 102488

Received:2018-08-29 Online:2019-07-15 Published:2019-10-29

摘要/Abstract

摘要： 本文阐述了单球中子谱仪的原理,介绍了基于单慢化球和19对⁶Li-⁷Li闪烁体探测器构成的单球中子谱仪的结构及解谱方法,使用蒙特卡罗中子输运程序模拟了单球中子谱仪的中子响应函数。计算结果表明,该谱仪具有较好的空间对称性,能根据谱仪中各探测器的计数对源的大致方位进行判断;模拟了单球谱仪在²⁴¹Am-Be源照射下各探测器的计数,使用Unfolding with Maxed and Gravel (UMG)解谱程序在不同解谱算法以及初始谱的情况下对模拟数据进行解谱计算,在使用最大熵散发以及与源项相同的预置谱的情况下,解谱结果最为准确,验证了响应函数的准确性。

关键词: 单球中子谱仪, 蒙特卡罗模拟, ⁶Li-⁷Li闪烁体探测器, 能量响应, 解谱

Abstract: The principle and structure of the single sphere neutron spectrometer based on a spherical polyethylene moderator with 19 pairs of ⁶Li and ⁷Li scintillation detectors was described in this paper. Calculated neutron response functions by Monte Carlo Neutron-particle Transport Code showed that this spectrometer has good spatial symmetry, and the source location can be estimated by detector’s counts. Simulated spectrometer was exposed in ²⁴¹Am-Be radiation field to obtain counts of each detector and to unfold the simulated results by using Unfolding with Maxed and Gravel (UMG) code to get the energy spectrum. Different algorithms and default spectrum were considered in unfolding process. Compared with expected spectrum, the spectrum unfolded by default spectrum of ²⁴¹Am-Be standard source and maximum entropy method is the most accurate. The accuracy of response function is verified.

Key words: single sphere neutron spectrometer, monte carlo simulation, ⁶Li and ⁷ Li scintillator detectors, energy response, spectrum unfolding

中图分类号:

TL72

邹益晟, 肖德涛, 张伟华, 王志强, 刘毅娜, 李春娟. 单球中子谱仪的能量响应模拟及解谱方法研究[J]. 辐射防护, 2019, 39(4): 280-286.

ZOU Yisheng, XIAO Detao, ZHANG Weihua, WANG Zhiqiang, LIU Yina, LI Chunjuan. Energy response simulation and unfolding method research ofsingle sphere neutron spectrometer[J]. RADIATION PROTECTION, 2019, 39(4): 280-286.

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