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arXiv · 1407.8133

Deep Photospheric Emission Lines as Probes for Pulsational Waves

Th. Rivinius·M. Shultz·G. A. Wade
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Abstract

Weak line emission originating in the photosphere is well known from O stars and widely used for luminosity classification. The physical origin of the line emission are NLTE effects, most often optical pumping by far-UV lines. Analogous lines in B stars of lower luminosity are identified in radially pulsating $\beta$ Cephei stars. Their diagnostic value is shown for radially pulsating stars, as these lines probe a much larger range of the photosphere than absorption lines, and can be traced to regions where the pulsation amplitude is much lower than seen in the absorption lines.

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Th. Rivinius, M. Shultz, G. A. Wade. 2014-07-30. Deep Photospheric Emission Lines as Probes for Pulsational Waves. https://doi.org/10.1017/s1743921314006826

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