Over much of the initial mass function, stars are destined to become luminous and cool red giants. They may then be able to produce dust in an atmosphere which has been elevated by strong radial pulsations, and hence drive a wind. The amount of mass that is lost in this way can be a very significant fraction of the stellar mass, and especially in the case of intermediate-mass stars it is highly enriched. The delay between a star's birth and its feedback into the environment varies from several million years for massive stars to almost the age of the Universe for the least massive red giants we see today. I here present a review on the metallicity dependence of red giant winds. I show that recent measurements not only confirm theoretical expectations, but also admonish of common misconceptions with implications for feedback at low initial metallicity.
Stellar Evolution at Low Metallicity: Mass Loss, Explosions, Cosmology
- Pub Date:
- December 2006
- Invited review for the 2005 Tartu workshop: Stellar Evolution at Low Metallicity: Mass Loss, Explosions, Cosmology, eds. H.J.G.L.M. Lamers, N. Langer, T. Nugis and K. Annuk, ASP Conference Series, in press