基于CTMC与ETACHA4的重离子在径迹上碰撞电离的研究  

Impact Ionization Investigation of Heavy Ion-Atom Along Penetration Tracks Based on CTMC and ETACHA4

作　　者：古敬仁 李国壮 张晟 李新霞[1] GU Jingren;LI Guozhuang;ZHANG Sheng;LI Xinxia(School of Nuclear Science and Technology,University of South China,Hengyang 421001,Hunan,China;Advanced Energy Science and Technology Guangdong Laboratory,Huizhou 516003,Guangdong,China;Institute of Modern Physics,Chinese Academy of Sciences,Lanzhou 730000,China;Center for Basic Teaching and Experiment,Nanjing University of Science and Technology,Jiangyin 214443,Jiangsu,China;Interdisciplinary Center for Fundamental and Frontier Sciences,Nanjing University of Science and Technology,Jiangyin 214443,Jiangsu,China)

机构地区：[1]南华大学核科学技术学院,湖南衡阳421001 [2]先进能源科学与技术广东省实验室,广东惠州516003 [3]中国科学院近代物理研究所,兰州730000 [4]南京理工大学基础教学与实验中心,江苏江阴214443 [5]南京理工大学基础前沿交叉中心,江苏江阴214443

出　　处：《原子核物理评论》2024年第4期1085-1091,共7页Nuclear Physics Review

基　　金：国家自然科学基金资助项目(11775108);湖南省研究生创新基金项目(QL20220210);先进能源科学与技术广东省实验室项目课题(DJLTN01020000)。

摘　　要：离子束驱动是产生高能量密度物质的重要途径,研究在穿透径迹上离子电荷态的变化以及产生电离电子的情况,对认识离子束在靶中的能量沉积过程有重要意义。本工作提出了一种计算径迹上重离子碰撞电离的方法,首先采用ETACHA4程序计算了重离子(如He^(2+),U^(92+))穿透固体靶(如D,Pb)过程中能量与电荷态随入射深度的变化,再利用CTMC程序计算在径迹上碰撞电离产生的电离电子平均能量。结果表明,He^(2+)、U^(92+)与Pb靶碰撞时,电离电子能量集中在0~100 keV范围内,平均电离电子能量随入射深度增加而增加;当入射粒子能量较低时(~几十MeV/u),平均电离电子能量变化不显著。U^(92+)穿透D靶时,电离电子能量集中在100eV以内,平均电子能量几乎保持不变,维持在16~18eV。该结果对于推动离子束驱动高能量密度物质的数值模拟有一定的意义,也可以为靶设计提供参考。Ion beam driving is a critical method for producing high energy density materials.It is of great significance to study the change of ion charge state and the generation of ionized electrons on the penetration track for understanding the energy deposition process of ion beam in the target.A method for calculating impact ionization of heavy ions along the tracks is proposed in this paper.Firstly,the ETACHA4 code is used to calculate the energy and charge state with penetration depth in collisions of heavy ions(He^(2+),U^(92+))with solid targets(D,Pb).Then the CTMC code is used to obtain detailed results of impact ionization along the track.The results of He^(2+)and U^(92+)ions colliding with Pb target reveal that the energy of ionized electrons is concentrated in the 0~100 keV range,and the average ionized electron energy increases with the penetration depth.The average electron energy does not change considerably when the incident energy is modest(~tens of MeV/u).For U^(92+)ions colliding with D target,the average energy of ionized electrons is distributed below 100 eV,and it remains almost constant,maintaining at 16~18 eV.The results of this study can help to further the numerical simulation of high energy density materials driven by heavy ion beams,as well as serve as a reference for target design.

关 键 词：CTMC ETACHA4 重离子碰撞 电离电子 

分 类 号：O571.33[理学—粒子物理与原子核物理]