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arXiv · 0811.0750

R-matrix inner-shell electron-impact excitation of Fe$^{15+}$ including Auger-plus-radiation damping

G Y Liang·A D Whiteford·N R Badnell
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Abstract

We present results for the inner-shell electron-impact excitation of Fe$^{15+}$ using the intermediate-coupling frame transformation {\it R}-matrix approach in which Auger-plus-radiation damping has been included. The target and close-coupling expansions are both taken to be the 134 levels belonging to the configurations ${\rm 2s^22p^63}l$, ${\rm 2s^22p^53s3}l$, ${\rm 2s^22p^53p^2}$ and ${\rm 2s^22p^53p3d}$. The comparison of Maxwell-averaged effective collision strengths with and without damping shows that the damping reduction is about 30-40% for many transitions at low temperatures, but up to 80% for a few transitions. As a consequence, the results of previous Dirac $R$-matrix calculations (Aggarwal and Keenan, 2008) overestimate the effective collision strengths due to their omission of Auger-plus-radiation damping.

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G Y Liang, A D Whiteford, N R Badnell. 2008-11-05. R-matrix inner-shell electron-impact excitation of Fe$^{15+}$ including Auger-plus-radiation damping. https://doi.org/10.1088/0953-4075/41/23/235203

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