三维中子-光子输运蒙特卡罗程序MCMG发展了针对物质的碰撞机制，几何块、几何面动态可扩展， 随机数周期进一步扩大到261。可进行多群-连续截面耦合计算，多群散射展开到P5，并考虑了中子上散射，程序配备了通用和专用多群截面库。MCMG模拟取得了与MCNP程序和实验一致的结果，串行计算速度较MCNP快2~4倍，可进行上万处理器核的并行计算。

A collision mechanism based on material rather than nuclide is added in the 3D Monte Carlo neutron and photon transport parallel code MCMG. Geometry cells and surfaces can be dynamically extended. The period of the random number is extended to 261. Combination of multigroup and continuous cross-section transport is developed. The multigroup scattering is expanded to P5 and the upper scattering is considered. Various multigroup libraries can be easily equipped in the code. The same results with the experiments and the MCNP code are obtained for a series of modes. The computation speed of MCMG is 2-4 times faster than the MCNP code.