Massive star feedback - from the first stars to the present

Jorick S. Vink

Keele University, UK

The amount of mass loss is of fundamental importance to the lives and deaths of very massive stars, their input of chemical elements and momentum into the interstellar and intergalactic media, as well as their emitted ionizing radiation. I review mass-loss predictions for hot massive stars as a function of metal content for groups of OB stars, Luminous Blue Variables, and Wolf-Rayet stars. Although it is found that the predicted mass-loss rates drop steeply with decreasing metal content (Mdot ~ Z^{0.7-0.85}), I highlight two pieces of physics that are often overlooked in cosmologocal studies: (i) mass-loss predictions for massive stars approaching the Eddington limit, and for (ii) stars that have enriched their own atmospheres with primary elements such as carbon. Both of these effects may significantly boost the mass-loss rates of the first stars -- relevant for the reionization of the Universe, and a potential pre-enrichment of the intergalactic medium -- prior to the first supernova explosions.

Reference: Vink, 2006, in: "Stellar Evolution at Low Metallicity: Mass-Loss, Explosions, Cosmology", eds: H. Lamers, N. Langer, T. Nugis), ASP Conf Series
Status: Conference proceedings


Comments: Invited Review in Tartu workshop, Aug 2005.