Energy levels, radiative rates, and electron impact excitation rates for transitions in O VII
Abstract
Aims: In this paper we report calculations for energy levels, radiative rates, and electron impact excitation rates for transitions in O vii.
Methods: The grasp (general-purpose relativistic atomic structure package) is adopted for calculating energy levels and radiative rates. For determining the collision strengths and subsequently the excitation rates, the Dirac atomic R-matrix code (darc) and the flexible atomic code (fac) are used.
Results: Oscillator strengths, radiative rates, and line strengths are reported for all E1, E2, M1, and M2 transitions among the lowest 49 levels of O vii. Collision strengths have been averaged over a Maxwellian velocity distribution, and the resulting effective collision strengths are reported over a wide temperature range below 2×106 K. Additionally, lifetimes are also listed for all levels.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- October 2008
- DOI:
- 10.1051/0004-6361:200810531
- Bibcode:
- 2008A&A...489.1377A
- Keywords:
-
- atomic data;
- atomic processes