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Line-profile variations in pulsating subdwarf-B stars as a pulsation mode diagnostic

C. Schoenaers·A. E. Lynas-Gray
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Abstract

In previous attempts to perform seismic modelling of pulsating subdwarf-B stars, various mode identification techniques are used with uncertain results. We investigated a method so far neglected in sdB stars, but very successful for Main Sequence pulsators, that is, mode identification from the line-profile variations caused by stellar pulsation. We report the calculation of time-resolved synthetic spectra for sdB stars pulsating with various combinations of pulsation modes; these calculations were carried out over appropriate ranges of effective temperature, surface gravity and helium abundances. Preliminary tests using these synthetic line-profile variations demonstrated their potential for mode identification by comparison with observation.

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C. Schoenaers, A. E. Lynas-Gray. 2005-11-01. Line-profile variations in pulsating subdwarf-B stars as a pulsation mode diagnostic. https://arxiv.org/abs/astro-ph/0511038

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