I review existing methods for determining mass-loss rates of red giants and red supergiants based on infrared data. The simplest method is based on models for the absorption and emission by dust which forms in the dense outflows from these cool stars. I discuss the parameters and assumptions upon which the method relies, review relationships between the mass-loss rate and infrared colors or far-infrared flux density, and propose a new formula for the mass-loss rate as a function of the visual extinction. I also briefly discuss the use of atomic and molecular transitions at infrared wavelengths.
Why Galaxies Care About AGB Stars: Their Importance as Actors and Probes
- Pub Date:
- November 2007
- Invited review, in: "Why Galaxies Care About AGB Stars", Vienna, August 2006, eds. Franz Kerschbaum, Corinne Charbonnel and Bob Wing, ASP Conference Series. It has 10 pages including one figure, a table with relationships between mass-loss rate and infrared colour, a few useful formulae and more than could be addressed in the conference presentation