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On the Structure of the Iron K-Edge

P. Palmeri·C. Mendoza·T. R. Kallman·M. A. Bautista
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Abstract

It is shown that the commonly held view of a sharp Fe K edge must be modified if the decay pathways of the series of resonances converging to the K thresholds are adequately taken into account. These resonances display damped Lorentzian profiles of nearly constant widths that are smeared to impose continuity across the threshold. By modeling the effects of K damping on opacities, it is found that the broadening of the K edge grows with the ionization level of the plasma and that the appearance at high ionization of a localized absorption feature at 7.2 keV is identified as the K-beta unresolved transition array.

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P. Palmeri, C. Mendoza, T. R. Kallman, M. A. Bautista. 2002-09-13. On the Structure of the Iron K-Edge. https://doi.org/10.1086/344243

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