锂原子光电离截面的无穷阶计算(英文)

The infinite-order calculations for the photoionization cross sections of lithium above thresholds

利用多体微扰理论,把基态锂原子K和L壳层电子的光电离过程中的电子相关效应计算到了无穷阶.用Feynman图技术讨论了基态关联效应和混相近似效应,并计算了与无穷阶末态关联的耦合效应.计算结果与实验和其他理论结果吻合得很好.

Using many-body perturbation theory (MBPT), the infinite-order perturbation calculations have been performed for the photoionization cross sections of the K and L shells in the ground state ls^22s^2S of the neutral lithium above the Li^+ls2s^3S, Li^+ls^(21)S thresholds respectively. The ground-state and random-phase approximation correlations coupled with infinite-order final-state correlations have been discussed by Feynman diagrams in detail. Comparison is made with other theoretical calculations and recent experimental results for the pure single photoionization of the K and L shells respectively. Very good agreement with experimental results has been obtained.