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arXiv · 1602.03452

The Variable Line Width of Achernar

Th. Rivinius·R. H. D. Townsend·D. Baade·A. C. Carciofi·N. Leister·S. Štefl
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Abstract

Spectroscopic observations of Achernar over the past decades, have shown the photospheric line width, as measured by the rotational parameter $v \sin i$, to vary in correlation with the emission activity. Here we present new observations, covering the most recent activity phase, and further archival data collected from the archives. The $v \sin i$ variation is confirmed. On the basis of the available data it cannot be decided with certainty whether the increased line width precedes the emission activity, i.e. is a signature of the ejection mechanism, or postdates is, which would make it a signature of re-accretion of some of the disk-material. However, the observed evidence leans towards the re-accretion hypothesis. Two further stars showing the effect of variable line width in correlation with emission activity, namely 66 Oph and $\pi$ Aqr, are presented as well.

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Th. Rivinius, R. H. D. Townsend, D. Baade, A. C. Carciofi, N. Leister, S. Štefl. 2016-02-10. The Variable Line Width of Achernar. https://arxiv.org/abs/1602.03452

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