Note on electron impact excitation for transition of Be-like isoelectronic sequence |
| |
Authors: | Chen Guo-xin PP Ong |
| |
Institution: | (1) Physics Department, National University of Singapore, Singapore 119260, SG |
| |
Abstract: | Relativistic distorted-wave method was used to calculate the electron impact excitation collision strengths for transitions
2
s2
1
S0-2
s
2
p
3
P1 of Be-like isoelectronic ions. The target states were described, respectively, by 10-level, 46-level and 133-level MCDF configuration-expansion.
The relativistic continuum orbitals were calculated in the potential field of frozen target-ion charge distribution with semi-classical
exchange potential. The influence of the target states on this collision process along the isoelectronic sequence was investigated
in the above three MCDF configuration-expansion modes. It was found that the configurations in the n
=3 and the n
=4 complexes have great influence on both the high and the low Z ions but the influence is relatively small for intermediate Z ions. The latter phenomenon was attributed to competition between opposing correlation and relativistic effects on the collision
strengths.
Received: 25 February 1998 / Received in final form: 18 June 1998 |
| |
Keywords: | PACS 34 50 Fa Electronic excitation and ionization of atoms (including beam-foil excitation and ionization)[:AND:] 34 80 Kw Electron-ion scattering excitation and ionization |
本文献已被 SpringerLink 等数据库收录! |