LBVs and the nature of the S Dor cycles: the case of AG Carinae
Abstract
We present the results of a detailed spectroscopic analysis of 20 years of observations of AG Carinae using the radiative transfer code CMFGEN. Among the conclusions of this work, we highlight the importance of including time-dependent effects in the analysis of the full S Dor cycle. We obtained that the mass-loss rate is approximately constant during the cool phases, implying that the S Dor-type eruptions begin well earlier than the maximum seen in the visual lightcurve. We also determined that the S Dor cycles are ultimately a consequence of an increase/decrease of the hydrostatic radius in combination with the formation of a pseudo-photosphere.
- Publication:
-
Revista Mexicana de Astronomia y Astrofisica Conference Series
- Pub Date:
- August 2008
- DOI:
- 10.48550/arXiv.astro-ph/0702612
- arXiv:
- arXiv:astro-ph/0702612
- Bibcode:
- 2008RMxAC..33..132G
- Keywords:
-
- stars: early-type;
- stars: individual (AG Car);
- stars: mass loss;
- Astrophysics
- E-Print:
- 2 pages, 2 figures, to appear in the Proceedings of "Massive Stars: Fundamental Parameters and Circumstellar Interactions"