强激光与高Z靶的相互作用——激光与等离子体相互作用的理论模拟(Ⅱ)

THE INTERACTIONS OF LASER BEAM WITH HIGH Z SOLID TARGET——COMPUTATIONAL SIMULATION OF THE INTERACTIONSFOR LASER WITH PLASMA(Ⅱ)

本文用一维非平衡辐射流体力学激光打靶程序JB—19模拟了强激光与高Z的金靶相互作用形成的等离子体状态。考虑的物理过程有:韧致效应,光电离和辐射俘获,电子碰撞电离和三体复合,电子碰撞激发和退激发,线辐射和线吸收以及康普顿散射过程等。 用波长1.06μm、脉宽600ps和峰值功率密度3×10^(14)W/cm^2的高斯型脉冲辐照厚约20μm的金圆盘靶,计算出的金靶对入射激光的吸收效率和激光—X光转换效率与国外实验结果基本一致。

The 1-D non-LTE radiative hydrodynamic laser irradiated code JB-19 is used to calculate the laser -produced plasma conditions of high z gold disk. Following physical processes are considered: bremsstrahlung effect, radiative ionization and recombination, collisional ionization by electrons and three -boby recombination, collisional excitation and de - excitation by electrons, radiative line emission and absorption and Compton scattering. A gaussian laser pulse with wavelength 1. 06μm, FWHM 600ps and peak intensity 3×1014W/cm2 is used to irradiate thickness 20μm gold disk. The computational results for laser- produced plasma conditions and the absorption efficiency and laser -x -rays conversion efficiency for gold disk are shown.