中子辐照育种样品吸收剂量率计算方法  

Calculation Method of Absorbed Dose Ratein Neutron Irradiation Breeding

作　　者：洪博 兰长林[1] 曹磊 郭志琦 潘小东[1] HONG Bo;LAN Changlin;CAO Lei;GUO Zhiqi;PAN Xiaodong(School of Nuclear Science and Technology,Lanzhou University,Lanzhou 730000,China)

机构地区：[1]兰州大学核科学与技术学院,兰州730000

出　　处：《现代应用物理》2022年第2期137-141,187,共6页Modern Applied Physics

基　　金：国家自然科学基金资助项目(711675069)。

摘　　要：针对中子辐照育种过程中样品中子吸收剂量率计算过程繁琐和计算结果不准确等问题,利用射线传递给样品的能量等效吸收剂量和吸收剂量率随离源距离的增大呈平方反比衰减的关系,推导出不同位置处样品吸收剂量率的计算公式,为中子辐照育种吸收剂量率的计算提供了新方法。以兰州大学Am-Be中子辐照场辐照拟南芥种子样品,使用该方法计算了拟南芥种子样品距中子源5 cm处的吸收剂量率为1.13×10^(-6)Gy·s^(-1)。利用MCNP模拟了该位置拟南芥种子样品的中子吸收剂量率为1.02×10^(-6)Gy·s^(-1),对比分析2种方法的计算结果,利用中子分群理论对新方法的计算结果进行修正,修正后2种方法的计算结果吻合程度较高。本文提出方法可为非辐射物理专业工作人员快速计算中子场中样品吸收剂量率提供参考。In the process of neutron irradiation breeding,there are some problems in calculating the neutron absorbed dose rate of samples,such as complicated process and inaccurate calculation results.In this paper,based on the energy equivalent absorbed dose that ray transmitted to samples and according to the theory that neutron flux decays in inverse square with the increase of distance from the source,the calculation formula of the sample absorbed dose rates at different positions is deduced,which provides a new method for the calculation of absorbed dose rate of neutron irradiation breeding.The Am-Be neutron source experimental hall of Lanzhou University is used to irradiate Arabidopsis seed samples.The absorbed dose rate of Arabidopsis seed sample is 1.13×10^(-6)Gy·s^(-1) at position of 5 cm away from the neutron source by using this formula.At the same time,the neutron absorbed dose rate of Arabidopsis seed sample is 1.02×10^(-6)Gy·s^(-1) by MCNP simulation.The calculation results of the two methods are compared and analyzed,and the neutron cluster theory is proposed to modify the calculation results of the new method.The calculation results of the two methods are in good agreement.This paper provides a reference method for non professional workers to quickly calculate the neutron absorption rate of radiation samples in the physical radiation field.

关 键 词：中子源 辐照育种 吸收剂量率 

分 类 号：TL99[核科学技术—核技术及应用] O571[理学—粒子物理与原子核物理]