国内典型地区地面大气中子能谱测量与仿真

基于多球能谱仪开展了广州、兰州和拉萨等地区的大气中子能谱和通量测量，获取了大气中子能谱的典型特征。测量结果表明：不同地区的大气中子通量受海拔高度的影响明显，地面大气中子通量随着海拔的增加而增加。此外，基于蒙特卡罗仿真工具也可以模拟初级宇宙射线粒子在地球大气层中的核反应过程，从而计算获取大气中子能谱。大气中子能谱测量数据与仿真数据吻合良好。

Measurement and simulation of terrestrial atmospheric neutron spectrum in typical regions of China

Atmospheric neutrons can cause the single event effect (SEE) of integrated circuits, resulting in data loss or functional interrupt. The SEE failure rate caused by atmospheric neutrons depends on its flux, thus obtaining the atmospheric neutron flux is the premise of SEE failure rate assessment. In this paper, the atmospheric neutron energy spectra and fluxes in Guangzhou, Lanzhou and Lhasa are measured using the Bonner sphere spectrometers (BSS). Typical characteristics of atmospheric neutron spectrum are obtained. The measured results show that the atmospheric neutron flux in different areas is affected by the altitude, and the terrestrial atmospheric neutron flux increases with the altitude. In addition, the nuclear reaction process of primary cosmic ray particles in the earth’s atmosphere can also be simulated based on the Monte Carlo simulation tools, so as to calculate the atmospheric neutron spectrum. It shows that the measured data of atmospheric neutron spectra are in good agreement with the simulation data. These data can be used in quantitative evaluation of atmospheric neutron-induced SEE of integrated circuits.