Electron Impact Excitation of O III: An Assessment

K M Aggarwal

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arXiv · 2103.02581

Electron Impact Excitation of O III: An Assessment

K M Aggarwal

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Abstract

Tayal and Zatsarinny [Astrophys. J. 850 (2017) 147] have reported results for energy levels, radiative rates (A-values), lifetimes, and effective collision strengths ($\Upsilon$) for transitions among 202 levels of C-like O~III. For the calculations they have adopted the multi-configuration Hartree-Fock (MCHF) code for the energy levels and A-values, and B-spline $R$-matrix (BSR) code for $\Upsilon$. Their reported results cover a (much) larger range of levels/transitions than generally available in the literature, and appear to be accurate for energy levels and A-values. However, the magnitude and behaviour of $\Upsilon$ do not appear to be correct for several transitions. We demonstrate this through our independent calculations by adopting the flexible atomic code (FAC) and recommend a fresh calculation for this important ion.

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K M Aggarwal. 2021-03-03. Electron Impact Excitation of O III: An Assessment. https://arxiv.org/abs/2103.02581

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