The HI Mass-Star Formation Rate Relation and Self-Regulated Star Formation in Dwarf Galaxies
Abstract
Description
We have developed a simple, static model designed to place a very solid lower limit on the star formation rate (SFR) expected in a dwarf disk galaxy, which leads to the prediction of a previously undocumented relation between HI mass, M_HI, and SFR. Over the mass range 10^8--10^10 M_sun, a wide variety of galaxies are observed to follow such a relation -- SFR ~ M_HI^1.4 -- with the same slope and similar scatter to our prediction. Within the model, this relation is a manifestation of self-regulating star formation (SF), in which the ISM is kept warm and stable by a UV interstellar radiation field (ISRF) that is maintained by constant regeneration of O--B stars. Regardless of the actual mode of star formation, it seems that the majority of dwarfs are presently forming stars in the same way.
Proceedings for the 5th Marseille International Cosmology Conference: The Fabulous Destiny of Galaxies; 2 pages, 1 figure; v2: updated figure and references
Proceedings for the 5th Marseille International Cosmology Conference: The Fabulous Destiny of Galaxies; 2 pages, 1 figure; v2: updated figure and references