Speaker
Dr
Patrick Palmeri
(Physique Atomique et Astrophysique, Université de Mons - UMONS, B-7000 Mons, Belgium)
Description
X-ray emission lines from accreting black holes, most notably K-lines, have observed
widths and shifts which imply an origin very close to the compact object [1]. The
intensity of these lines can provide insight into the effects of special and general relativity
in the emitting region as well as insight into some properties of the compact object itself.
Magnetohydrodynamics simulations of accreting black holes computed by Schnittman et al. [2] seem to reveal that the plasma conditions in such an environment should be characterized by an electronic temperature ranging from $10^5$ to $10^7$ K and an electronic density ranging from $10^{18}$ and $10^{21}$ cm$^{-3}$. This may affect the atomic structure and processes corresponding to the ionic species present in the plasma.
The main goal of the present work is thus to estimate the effects of plasma environment on the atomic parameters associated with the K-vacancy states in cosmically abundant ions within the astrophysical context of accretion disks around black holes. In order to do this, relativistic atomic structure calculations have been carried out by using the multiconfiguration Dirac-Fock (MCDF) method, in which a time averaged Debye-Hückel potential have been considered for both the electron-nucleus and electron-electron interactions for modeling the plasma environment. Those computations have been performed by using a combination of the GRASP92 code [3] for obtaining the wavefunctions and the RATIP code [4] for computing the atomic parameters, taking into account the plasma environment.
A new set of results related to the plasma environment effects on ionization potentials, transition energies and radiative emission rates is reported for some iron and oxygen ions. A comparison between the atomic parameters obtained by using the MCDF method and another independent computational approach, namely the Breit-Pauli relativistic approximation as implemented in the AUTOSTRUCTURE code [5,6], will also be discussed in detail.
1. C.S. Reynolds and M.A. Nowak, Phys. Rep. 377, 389, 2003.
2. J.D. Schnittman, J.H. Krolik and S.C. Noble, Astrophys. J. 769, 156, 2013.
3. F.A. Parpia, C. Froese Fischer and I.P. Grant, Comput. Phys. Commun. 94, 249, 1996.
4. S. Fritzsche, Comput. Phys. Commun. 183, 1523, 2012.
5. N.R. Badnell, J. Phys. B : At. Mol. Opt. Phys. 30, 1, 1997.
6. N.R. Badnell, Comput. Phys. Commun. 182, 1528, 2011.
Primary authors
Mr
Jérôme Deprince
(Physique Atomique et Astrophysique, Université de Mons - UMONS, B-7000 Mons, Belgium)
Dr
Patrick Palmeri
(Physique Atomique et Astrophysique, Université de Mons - UMONS, B-7000 Mons, Belgium)
Co-authors
Dr
Claudio Mendoza
(Department of Physics, Western Michigan University, Kalamazoo, MI 49008, USA)
Dr
Javier Garcia
(Department of Astronomy, California Institute of Technology, Pasadena, CA 91125, USA)
Prof.
Manuel A. Bautista
(Department of Physics, Western Michigan University, Kalamazoo, MI 49008, USA)
Dr
Pascal Quinet
(Physique Atomique et Astrophysique, Université de Mons - UMONS, B-7000 Mons, Belgium)
Prof.
Stephan Fritzsche
(Helmholtz Institut Jena, 07743 Jena, Germany)
Dr
Timothy R. Kallman
(NASA Goddard Space Flight Center, Code 662, Greenbelt, MD 20771, USA)
