激光金等离子体的电子离子碰撞电离速率系数

电子离子碰撞电离过程在超组态碰撞辐射(SCROLL)模型中真实模拟非局域热动力学平衡(non-LTE)高Z材料Au激光等离子体M带谱5f-3d跃迁中各种复杂离子的电离态特性,诸如离子的平均电离度和电荷态分布是一个主要过程.基于准相对论扭曲波玻恩交换近似,采用组态平均的方法,从头计算了金M带类铁金离子-类锗金离子的电子离子碰撞电离速率系数,其中电离截面的高能行为由Bethe系数决定.结果表明:在"神光Ⅱ"实验装置诊断的电子温度～2keV,电子密度～6×1021cm-3范围内,这些参数有利于使用超组态碰撞辐射模型拟Au的激光等离子体M带细致谱5f-3d跃迁的平均电离度和电荷态分布.

Collisional ionization rate coefficients of electron impact ionization in a highly ionized Au plasma

Electron impact ionization rate coefficients among configuration average levels from Fe like Au 53+ to Ge like Au 47+ ions have been calculated systematically based on Cowan's quasi relativistic multi configuration Hartree Fock Relativistic code and distorted wave approachs. We have related the scaled cross sections to the Bethe coefficients at high energy regime. The latter can be obtained by integral of cross section of photoionization. According to our calculations, the scaled cross sections vary slowly as the charge state charge. These cross sections are then fit to obtain corresponding rate coefficients. It is feasible to simulate the average ionized state and ionic abundance and charge state distribution in the diagnosed electron temperature ～2 keV in a well characterize highly ionized Au Plasma.