利用全相对论组态相互作用方法,详细研究了W44+离子从基组态3s23p63d104s2俘获一个电子形成双激发态(3s23p63d104s2)1nln′l′(n=4~6,n′=4~7)的双电子复合(DR)过程。通过比较不同壳层电子激发的DR速率系数,得知4s电子激发和3d电子激发的DR速率系数分别在低温和中高温度时给出了主要贡献,得到了主要的电子激发DR通道。在1 eV~50 keV温度范围内,计算了n=4~18的DR速率系数,并外推到了n=100,得到总DR速率系数。比较总DR速率系数、三体复合(TBR)以及辐射复合(RR)速率系数,结果表明DR速率系数在研究的温度范围内远大于TBR和RR速率系数,其将明显地影响ITER等离子体的电离平衡和离化态布居。
Based on the fully relativistic configuration interaction method, theoretical calculations are carried out to research the dielectronic recombination (DR) processes, in which W44+ ions in the ground state 3s23p63d104s2 trap an electron to form doubly excited states (3s23p63d104s2)1nln′l′(n=4~6,n′=4~7). The comparison of the DR rate coefficients of different shells shows that DR approach is as follow: the 4s subshell excitation dominates to DR at low temperature, but 3d subshell excitation attributes to DR at high temperature. Total DR rate coefficients from n=4-18 are evaluated directly, and the results are extrapolated up to n = 100 in the temperature range from 1 to 5-104 eV, and thus get the total DR rate coefficients. Compared total DR rate coefficients to three-body recombination (TBR) rate coefficients and radiative recombination (RR) rate coefficients, it showed that the total DR rate coefficients obviously significantly greater than other two recombination rate coefficients, and thus it obviously influence ionization equilibrium and ionization state population of ITER plasma.