Photoionization Modeling and the K Lines of Iron
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Open Access
- 1 December 2004
- journal article
- research article
- Published by American Astronomical Society in The Astrophysical Journal Supplement Series
- Vol. 155 (2) , 675-701
- https://doi.org/10.1086/424039
Abstract
We calculate the efficiency of iron K line emission and iron K absorption in photoionized models using a new set of atomic data. These data are more comprehensive than those previously applied to the modeling of iron K lines from photoionized gases and allow us to systematically examine the behavior of the properties of line emission and absorption as a function of the ionization parameter, density, and column density of model constant density clouds. We show that, for example, the net fluorescence yield for the highly charged ions is sensitive to the level population distribution produced by photoionization, and these yields are generally smaller than those predicted assuming the population is according to statistical weight. We demonstrate that the effects of the many strongly damped resonances below the K ionization thresholds conspire to smear the edge, thereby potentially affecting the astrophysical interpretation of absorption features in the 7-9 keV energy band. We show that the centroid of the ensemble of Kα lines, the Kβ energy, and the ratio of the Kα1 to Kα2 components are all diagnostics of the ionization parameter of our model slabs.Keywords
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This publication has 39 references indexed in Scilit:
- K-shell photoionization and electron impact excitation of Fe XVII–Fe XXIIIAstronomy & Astrophysics, 2004
- Atomic data for the K-vacancy states of Fe XXIVAstronomy & Astrophysics, 2003
- Inner-shell processes of Li- and Be-like FeJournal of Physics B: Atomic, Molecular and Optical Physics, 2001
- Inner-shell photoionization of the 3dxground state Fe ionsJournal of Physics B: Atomic, Molecular and Optical Physics, 2001
- Resonance‐averaged Photoionization Cross Sections for Astrophysical ModelsThe Astrophysical Journal Supplement Series, 1998
- The calculation of high-energy photoionization cross sections for the Be isoelectronic sequenceJournal of Physics B: Atomic, Molecular and Optical Physics, 1997
- On the effects of the two-body non-fine-structure operators of the Breit - Pauli HamiltonianJournal of Physics B: Atomic, Molecular and Optical Physics, 1997
- High-resolution measurements, line identification, and spectral modeling of K-alpha transitions in Fe XVIII-Fe XXVThe Astrophysical Journal, 1993
- Experimental study of the x-ray transitions in the heliumlike isoelectronic sequencePhysical Review A, 1989
- Dielectronic satellite spectra for He-like ionsAtomic Data and Nuclear Data Tables, 1986