类铍C III, N IV, O V离子的基态和亚稳态的直接单电离截面计算

本文使用相对论扭曲波近似计算了基态(1s22s2 1S)和亚稳态(2s2p 3P)的类铍C III, N IV和O V离子的电子碰撞直接单电离截面。计算中包括了基态的2s壳层和亚稳态的2s、2p壳层的直接单电离而没有包括1s子壳层。其结果与现有的理论和实验数据进行了比较，相对论扭曲波近似结果在外型和大小上都与近期的实验数据很一致，且与其他理论结果相比，在近阈和高能范围内与实验数据符合得更好。

Direct single ionization cross sections for the ground and metastable states of Be-like C III, N IV and O V

The direct single ionization cross sections for the ground (1s22s2 1S) and metastable states (2s2p 3P) of Be-like C III, N IV and O V are calculated using relativistic distorted-wave (RDW) approach. The direct single ionization of 2s for ground state and 2s, 2p for metastable state are included but the ionization of 1s shell is not included. Comparison with available theoretical and experimental data has been made. The present results are in excellent agreement with the recent experimental measurements in both shape and magnitude. The present results of RDW approach achieve a better agreement with recent experimental results than other theoretical results in threshold and high energy range.