The Variable Line Width of Achernar
Abstract
Spectroscopic observations of Achernar over the past decades, have shown the photospheric line width, as measured by the rotational parameter , 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 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 Aqr, are presented as well.
Cite
@article{arxiv.1602.03452,
title = {The Variable Line Width of Achernar},
author = {Th. Rivinius and R. H. D. Townsend and D. Baade and A. C. Carciofi and N. Leister and S. Štefl},
journal= {arXiv preprint arXiv:1602.03452},
year = {2016}
}
Comments
To appear in conference proceedings "Bright Emissaries: Be Stars as Messengers of Star-Disk Physics", eds. A. Sigut and C. Jones (11 Aug 2014 - 13 Aug 2014, London, Ontario, Canada)