细致能级光电离与辐射复合速率系数的计算及讨论

在以前所计算的细致能级光电过程截面数据的基础上,用修正的Gramm-Schmidt方法做三次样条函数的最小二乘拟合,在LTE近似条件下,取光子分布函数为Planck分布,自由电子分布函数为Maxwel分布,给出了光电离与辐射复合速率系数积分在样条参数下的表达式,并计算了类氦铷、类氦铌离子光电离与辐射复合速率系数。分析了能级跃迁下的速率系数向轨道跃迁速率系数的过渡关系,并对文1]给出的半经验公式进行了评价。

THE CALCULATION AND DISCUSSION OF DETAILED PHOTOIONIZATION AND RADIATIVE RECOMBI-NATION RATE COEFFICIENTS

The corrected Gramm-Schmidt method is employed in 3-splined fitting of photoionization cross sections which was calculated in the authors previous work.In the case of LTE approximation,photon and free electron are assumed to be in Planck and Maxwell distribution respectively.The present derivation shows that,the rate coefficients of photoionization and radiative recombination can be described analytically in terms of 3-splined fitting parameters.This formulation is applied to He-like Rb and He-like Nb ions,and some of the results are figured out and analysed.By means of averaging over initial states and summing over final states,the degeneration of rate coefficients that concern the level level transitions is analysed explicitely.With the attained result, comparison and evaluation have been made to the formula given by reference1].