A comparison of light and velocity variations in semiregular variables

Author(s)
Thomas Lebzelter
Abstract

NIR velocity variations are compared with simultaneous visual light curves for a sample of late-type semiregular variables (SRV). Precise radial velocity measurements are also presented for the SRV V450 Aql. Our aim is to investigate the nature of the irregular light changes found in these variables. Light and velocity variations are correlated in all stars of our sample. Based on these results we discuss several possibilities to explain the observed behavior. We find that pulsation is responsible for large amplitude variations. In a recent paper Lebzelter (1999) invoked large convective cells to understand observed velocity variations. This possibility is discussed with respect to the observed correlation between light and velocity changes. In the light of these results we investigate the origin of the semiregular variations.

Organisation(s)
Department of Astrophysics
Journal
Astronomy & Astrophysics
Volume
361
Pages
167-174
No. of pages
8
ISSN
0004-6361
Publication date
2000
Peer reviewed
Yes
Austrian Fields of Science 2012
103003 Astronomy
Portal url
https://ucrisportal.univie.ac.at/en/publications/7ca10f97-816a-44f3-b7bb-c5e1c7544fc0