高能离子在稠密等离子体中的能量沉积和电子离子能量分配  

Energy deposition and electron-ion energy partition of high-energy ions in dense plasmas

作　　者：李子健 林成亮 吴勇[1] 王建国[1] LI Zijian;LIN Chengliang;WU Yong;WANG Jianguo(National Key Laboratory of Computational Physics,Institute of Applied Physics and Computational Mathematics,Beijing 100088,China)

机构地区：[1]北京应用物理与计算数学研究所,计算物理全国重点实验室,北京100088

出　　处：《物理学报》2025年第9期124-132,共9页Acta Physica Sinica

基　　金：国家重点研发计划(批准号:2022YFA1602500);国家自然科学基金(批准号:12474277,U2430208)资助的课题。

摘　　要：高能粒子在等离子体中的能量沉积及其导致的电子离子能量分配对理解惯性约束聚变的点火和燃烧过程至关重要.基于量子动理学的T矩阵扩展模型,本文研究了宽广温度密度区间的能量沉积和电子能量分配因子.相较于基于小角度散射的阻止本领模型,T矩阵扩展模型能考虑由大角度库仑散射及其累积过程带来的横向偏转效应.首先研究了横向偏转效应对电子能量分配因子的影响,然后计算了宽温度密度区间的电子能量分配因子,基于这些数据的分析发展了适用于惯性约束聚变模拟的电子能量分配因子拟合表达式.研究发现,考虑横向偏转效应会给电子能量分配因子带来约27.5%的差异.这一结论表明,准确描述高能粒子能量沉积过程中的大角度库仑散射及其累积效应带来的横向偏转会影响惯性约束聚变点火和燃烧模拟的精确性.Energy deposition of high-energy ions and the resulting electron-ion energy partition in dense plasmas are of essential importance in understanding the hot-spot ignition and burning of inertial confinement fusion.In this work,the energy deposition and electron-ion energy partition of high-energy ions are studied in a wide range of temperatures and densities based on the improved T-matrix model.Compared with the stopping power model based on the assumption of small-angle scattering,the improved T-matrix model can consistently take into account the large-angle Coulomb scattering and the resulting transversal deflection of the high-energy ions.We investigate the influence of the effect of transversal deflection on the electron-ion energy partition and propose a fitting formula for the energy partition fraction to plasma electrons.This formula is applicable to inertial confinement fusion simulations.It is found that when the effect of transversal deflection is considered,the relative energy deposited into electrons in plasma is reduced by about 27.5%at most.This conclusion suggests that the transversal deflection of energetic ions,induced by the large-angle Coulomb scattering and its cumulative effect,ought to be considered in accurately simulating the hot-spot ignition and burning of the fuel in inertial confinement fusion.

关 键 词：能量沉积 电子离子能量分配 非理想等离子体 惯性约束聚变 

分 类 号：O53[理学—等离子体物理]