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arXiv · 1107.3146

K-shell photoionization of Nickel ions using R-matrix

M. C. Witthoeft·M. A. Bautista·J. Garcia·T. R. Kallman·C. Mendoza·P. Palmeri·P. Quinet
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Abstract

We present R-matrix calculations of photoabsorption and photoionization cross sections across the K edge of the Li-like to Ca-like ions stages of Ni. Level-resolved, Breit-Pauli calculations were performed for the Li-like to Na-like stages. Term-resolved calculations, which include the mass-velocity and Darwin relativistic corrections, were performed for the Mg-like to Ca-like ion stages. This data set is extended up to Fe-like Ni using the distorted wave approximation as implemented by AUTOSTRUCTURE. The R-matrix calculations include the effects of radiative and Auger dampings by means of an optical potential. The damping processes affect the absorption resonances converging to the K thresholds causing them to display symmetric profiles of constant width that smear the otherwise sharp edge at the K-shell photoionization threshold. These data are important for the modeling of features found in photoionized plasmas.

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M. C. Witthoeft, M. A. Bautista, J. Garcia, T. R. Kallman, C. Mendoza, P. Palmeri, P. Quinet. 2011-07-15. K-shell photoionization of Nickel ions using R-matrix. https://doi.org/10.1088/0067-0049/196/1/7

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