Plasma environment effects on K lines of astrophysical interest

I. Atomic structure, radiative rates, and Auger widths of oxygen ions

¹ Physique Atomique et Astrophysique, Université de Mons – UMONS, 7000 Mons, Belgium
e-mail: patrick.palmeri@umons.ac.be
² Department of Physics, Western Michigan University, Kalamazoo, MI 49008, USA
³ Helmholtz Institut Jena, 07743 Jena, Germany
⁴ Theoretisch Physikalisches Institut, Friedrich Schiller Universität Jena, 07743 Jena, Germany
⁵ Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA 91125, USA
⁶ Dr. Karl Remeis-Observatory and Erlangen Centre for Astroparticle Physics, Sternwartstr. 7, 96049 Bamberg, Germany
⁷ NASA Goddard Space Flight Center, Code 662, Greenbelt, MD 20771, USA
⁸ IPNAS, Université de Liège, Sart Tilman, 4000 Liège, Belgium

Received: 17 January 2019
Accepted: 4 March 2019

Abstract

Aims. In the context of black-hole accretion disks, the main goal of the present study is to estimate the plasma environment effects on the atomic structure and radiative parameters associated with the K-vacancy states in ions of the oxygen isonuclear sequence.

Methods. We used a time-averaged Debye–Hückel potential for both the electron–nucleus and the electron–electron interactions implemented in the fully relativistic multiconfiguration Dirac–Fock (MCDF) method.

Results. Modified ionization potentials, K thresholds, Auger widths, and radiative transition wavelengths and rates are reported for O I–O VII in plasma environments with electron temperature and density ranges 10⁵−10⁷ K and 10¹⁸−10²² cm⁻³.