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arXiv · 1003.5161

Dielectronic Recombination of Argon-Like Ions

Abstract

We present a theoretical investigation of dielectronic recombination (DR) of Ar-like ions that sheds new light on the behavior of the rate coefficient at low-temperatures where these ions form in photoionized plasmas. We provide results for the total and partial Maxwellian-averaged DR rate coefficients from the initial ground level of K II -- Zn XIII ions. It is expected that these new results will advance the accuracy of the ionization balance for Ar-like M-shell ions and pave the way towards a detailed modeling of astrophysically relevant X-ray absorption features. We utilize the AUTOSTRUCTURE computer code to obtain the accurate core-excitation thresholds in target ions and carry out multiconfiguration Breit-Pauli (MCBP) calculations of the DR cross section in the independent-processes, isolated-resonance, distorted-wave (IPIRDW) approximation. Our results mediate the complete absence of direct DR calculations for certain Ar-like ions and question the reliability of the existing empirical rate formulas, often inferred from renormalized data within this isoelectronic sequence.

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D. Nikolić, T. W. Gorczyca, K. T. Korista, N. R. Badnell. 2010-03-24. Dielectronic Recombination of Argon-Like Ions. https://doi.org/10.1051/0004-6361/201014485

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