Non-LTE modelling of the He I 10830 Å line in early-type main sequence stars
Dr. Remeis-Sternwarte Bamberg, Universität Erlangen-Nürnberg, Sternwartstrasse 7, 96049 Bamberg, Germany e-mail: firstname.lastname@example.org
Accepted: 3 July 2005
The near-IR 10 830 Å transition is a highly sensitive diagnostic for non-LTE effects in astrophysical plasmas. So far, non-LTE line-formation computations have failed to quantitatively reproduce observations of this line in the entire range of early-A to late-O main sequence stars. It is shown that the non-LTE modelling was insufficient, for the most part, either because of inaccurate photoionization cross-sections for the 2s 3S state or because of neglecting line blocking. New calculations based on state-of-the-art atomic data give excellent agreement with observation for the 10 830 Å feature, while profiles of the lines in the visual are retained.
Key words: line: formation / infrared: stars / stars: early-type
© ESO, 2005