低能α粒子与中子耦合输运模拟

Simulation of Alpha-neutron Coupled Transportation in the Low Energy Region

开发了低能α粒子与中子耦合输运程序,可以计算低能α粒子在各种介质中的输运、含氧介质中的(,αn)中子产额,跟踪次级中子。采用蒙特卡罗方法中带权重跟踪的技巧,通过大量小权重事件的模拟成功解决了低能(,αn)反应中子产额太低、无法直接模拟的困难。α粒子的射程与阻止本领用SR IM程序计算,(,αn)截面取自最新的JENDL带电粒子库,次级中子跟踪使用MCNP程序。

A new code package of alpha-neutron coupled transportation is developed. It can be used to simulate the transportation of alpha particle in media, to compute the neutron yield in media contains oxygen and to track the history of the secondary neutrons. The secondary neutrons are simulated efficiently by tracking lots of neutrons with small weight, which is determined by the alpha-neutron yield. The stopping power and range of alpha particle in media are given by SRIM code, the alpha-neutron cross section is from charged particle library in JENDL, and the neutrons are treated by MCNP code.