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arXiv · 1203.4877

Inelastic Mg+H collision data for non-LTE applications in stellar atmospheres

P. S. Barklem·A. K. Belyaev·A. Spielfiedel·M. Guitou·N. Feautrier
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Abstract

Rate coefficients for inelastic Mg+H collisions are calculated for all transitions between the lowest seven levels and the ionic state (charge transfer). The rate coefficients are based on cross-sections from full quantum scattering calculations, which are themselves based on detailed quantum chemical calculations for the MgH molecule. The data are needed for non-LTE applications in cool astrophysical environments, especially cool stellar atmospheres, and are presented for a temperature range of 500-8000 K. From consideration of the sensitivity of the cross-sections to various uncertainties in the calculations, most importantly input quantum chemical data and the numerical accuracy of the scattering calculations, a measure of the possible uncertainties in the rate coefficients is estimated.

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P. S. Barklem, A. K. Belyaev, A. Spielfiedel, M. Guitou, N. Feautrier. 2012-03-22. Inelastic Mg+H collision data for non-LTE applications in stellar atmospheres. https://doi.org/10.1051/0004-6361%2F201219081

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