80.5 MeV/u碳离子诱发铜靶的放射性剩余产物测量

Measurement of radioactive residual nuclides induced in Cu target by 80.5 MeV/u carbon ions

高能重带电粒子能直接穿透靶原子核外电子层,与原子核发生直接碰撞,发生散裂反应,产生一系列具有放射性的剩余产物核.重带电粒子诱发靶材放射性剩余核与辐射防护和人员安全有着密切联系,当前,大部分剩余核产额主要依靠蒙特卡罗粒子输运程序进行模拟计算,其准确程度亟需通过实验测量进行准确评估.本文利用能量为80.5 MeV/u的(12)^C^(6+)粒子对薄铜靶开展了辐照实验与伽玛射线测量,结合伽玛谱学分析方法,得出了辐照产生的18种放射性剩余产物的初始活度和产生截面值,并与PHITS模拟结果进行对比.结果表明,PHITS模拟程序对放射性剩余核种类的估计具有较高可靠性,在其绝对产额方面,与实验测量仍具有较大偏差.

Radioactive residual nuclides,which are usually closely related to radiation protection and personnel safety,will be generated when target materials are irradiated by high energy particles.Based on different nuclear reaction models,Monte Carlo code is a usual method to obtain residual nuclide production.The simulation accuracy needs to be evaluated by experimental data.In this paper,an irradiation experiment of thin copper target irradiated by (12)^C^(6+)particles with energy of 80.5 MeV/u is carried out.The radioactivities and crosssections of 18 radioactive residual nuclides are obtained by gamma spectrometry analysis.Compared with the Monte Carlo simulation by PHITS,the results show that the spallation model of PHITS has a high reliability in estimating the types of radioactive residual nuclei,and it could be optimized in the aspect of the absolute yield.