100 MeV质子降能材料的选择研究

Selection of Energy Degrader Material for 100 MeV Protons

降能器对于提升质子单粒子效应(SEE)地面模拟试验的效率具有重要意义,而降能材料的选择是降能器设计中的首要问题。计算了100 MeV质子在4种常见降能材料铍、石墨、铝、铜中产生的能量岐离、角度岐离、中子本底以及感生放射性等对质子SEE地面模拟试验有影响的4个方面,其中感生放射性的计算中包含了降能过程在材料中产生的放射性核素种类、活度及残余剂量率。根据以上计算结果,并结合质子SEE地面模拟试验的要求,在降低相同的能量这一情况下,对4种材料作为100 MeV质子降能材料的适用性进行了分析比较,最终选择铝作为100 MeV质子的降能材料,并将应用在中国原子能科学研究院100 MeV质子回旋加速器的质子SEE地面模拟试验装置的降能器设计中。

The energy degrader is of great significance for improving the efficiency of the proton single event effect(SEE)ground simulation tests,and the selection of the energy degrader materials is a primary problem in the energy degrader design.Four aspects that are of much concern in the proton SEE tests,i.e.,the energy straggling,angle straggling,neutron background and induced radioactivity,produced by 100 MeV protons in the energy degradation process in the four common energy degrader materials(beryllium,graphite,aluminium and copper)were calculated,respectively.In terms of the calculation of the induced radioactivity,the types,activities and residual dose rates of the radionuclides generated in the materials were included.According to the above calculation results,combined with the requirements of the proton SEE tests,the applicability of the four materials as the energy degrader material for 100 MeV protons was analyzed and compared in the case of the same energy degradation.Finally,aluminium was selected as the energy degrader material for 100 MeV protons employed by the proton SEE ground simulation test facility on the 100 MeV proton cyclotron of China Institute of Atomic Energy.