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arXiv · 1210.7893

A catalogue of Paschen-line profiles in standard stars

Wenjin Huang·George Wallerstein·Myra Stone
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Abstract

We have assembled an atlas of line profiles of the Paschen Delta line at 10,049 angstroms for the use of stellar modelling. For a few stars we have substituted the Paschen Gamma line at 10,938 angstroms because the Paschen Delta line blends with other features. Most of the targets are standard stars of spectral types from B to M. A few metal-poor stars have been included. For many of the stars we have also observed the Hydrogen Alpha line so as to compare the profiles of lines originating from the meta-stable n=2 level with lines originating from the n=3 level. The greatest difference in line profile is found for high luminosity and cool stars where the departures from LTE in the population of the n=2 level is expected to be the greatest. For a few stars, sample line profiles have been calculated in the LTE approximation to demonstrate the usefulness of the tabulated and displayed catalogue.

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Wenjin Huang, George Wallerstein, Myra Stone. 2012-10-30. A catalogue of Paschen-line profiles in standard stars. https://doi.org/10.1051/0004-6361/201219804

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