M-Shell Dielectronic Recombination: Theoretical Study

Journal Article · Tue Mar 10 00:00:00 EDT 2009 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.3119991· OSTI ID:21289503

Abdel-Naby, Sh A; Nikolic, D; Gorczyca, T W ^[1]; Badnell, N R ^[2]; Savin, D W ^[3]

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1. Department of Physics, Western Michigan University, Kalamazoo MI 49008-5252 (United States)
2. Department of Physics, University of Strathclyde, Glasgow G4 0NG (United Kingdom)
3. Columbia Astrophysics Laboratory, Columbia University, New York NY 10027 (United States)

Dielectronic recombination (DR) is an important atomic physics process that is relevant to astrophysical plasma modeling. DR is responsible for the charge state balance as well as the cooling of plasmas, and it is the dominant electron-ion recombination process for most ions in both photoionized and collisionally-ionized plasmas. Accurate and reliable calculations for DR rate coefficients are needed to analyze the spectra obtained from astrophysical observations. Over the past few years, our group has computed reliable DR and radiative recombination (RR) data for all isoelectronic sequences up through Mg-like ions using a state-of-the-art multi-configuration Breit-Pauli (MCBP) approach. Recently, we have focused our work on the complex third-row M-shell isoelectronic sequences, especially Al-like. Although there exist some DR calculations for S{sup 3+}, those calculations were performed only within a non-relativistic LS-coupling approximation and for electron-ionized, higher temperatures. Fe{sup 13+} DR calculations have been completed and tested against the Heidelberg heavy-ion Test Storage Ring facility measurements. Semi-relativistic DR cross section and rate coefficient calculations for Al-like S{sup 3+} using the level-resolved distorted-wave AUTOSTRUCTURE program will be presented. The effect of ground-state fine structure on the DR rates will be discussed. These calculations include final-state-resolved partial DR and RR rate coefficients from the initial ground and metastable levels spanning a temperature range of 10 z{sup 2} K-10{sup 7} z{sup 2} K, where z is the initial ionic charge. Our computed Maxwellian DR rate coefficients are fitted into a simple formula for efficient dissemination of data and ease of use in plasma modeling codes, and comparisons to existing data will be shown.

• OSTI ID: 21289503
• Journal Information: AIP Conference Proceedings, Vol. 1099, Issue 1; Conference: CAARI 2008: 12. international conference on application of accelerators in research and industry, Fort Worth, TX (United States), 10-15 Aug 2008; Other Information: DOI: 10.1063/1.3119991; (c) 2009 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
A CODES
CHARGE STATES
COMPARATIVE EVALUATIONS
COMPUTERIZED SIMULATION
CROSS SECTIONS
DISTORTED WAVE THEORY
ELECTRON-ION COLLISIONS
GROUND STATES
IRON IONS
L-S COUPLING
M SHELL
METASTABLE STATES
MULTICHARGED IONS
PHOTOIONIZATION
PLASMA SIMULATION
RECOMBINATION
SULFUR IONS