中子大气传输特性的Monte Carlo模拟

The Monte Carlo simulation of atomospheric transport of neurons

用MonteCarlo方法计算了中子通过大气传输到不同高度轨道探测器的中子注量和能谱。研究结果表明:到达不同轨道的中子的能谱结构相同,因此中子能谱的基本结构在大气传输过程中保持不变;在保持能谱基本结构不变的前提下,随中子的传输,其低能中子份额在缓慢增大,高能中子份额在缓慢减小;大气中的中子注量超过了自由空间中相应的中子注量;能谱及注量的研究结果同时证明了中子的大气传输主要受散射机制而不是吸收机制所控制。

Integrated flux and energy spectrum of neutron arriving at detector located in different orbit through atmosphere are calculated by Monte Carlo method. We conclude that energy spectrum of neutron arriving at different orbit is similar, energy spectrum of neutron keep invariable basically when transporting in atmosphere. Following the precondition proportion of low energy is slowly increasing and proportion of high energy is slowly decreasing. The integrated flux of neutron is larger in atmosphere than in free space. Basing on the above results atmospheric transport of neutron is mainly dominated by scattering effects not absorbing.