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arXiv · 1512.01118

Non-LTE iron abundances in cool stars: The role of hydrogen collisions

Rana Ezzeddine·Thibault Merle·Bertrand Plez
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Abstract

In the aim of determining accurate iron abundances in stars, this work is meant to empirically calibrate H-collision cross-sections with iron, where no quantum mechanical calculations have been published yet. Thus, a new iron model atom has been developed, which includes hydrogen collisions for excitation, ionization and charge transfer processes. We show that collisions with hydrogen leading to charge transfer are important for an accurate non-LTE modeling. We apply our calculations on several benchmark stars including the Sun, the metal-rich star α Cen A and the metal-poor star HD140283.

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Rana Ezzeddine, Thibault Merle, Bertrand Plez. 2015-12-03. Non-LTE iron abundances in cool stars: The role of hydrogen collisions. https://doi.org/10.1002/asna.201612384

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