upernova Feedback and the Formation of Disk Galaxies

SCANNAPIECO, C.; TISSERA, P. B.; WHITE, S. D.M.; SPRINGEL, V

From Stars to Galaxies: Building the Pieces to Build Up the Universe. ASP Conference Series

Año: 2007; p. 475 - 481

We study the effects of Supernova (SN) feedback on the formation of disk galaxies. For this purpose we run numerical simulations in a cosmological context using a version of the Tree-PM SPH code GADGET-2 which includes chemical enrichment and energy feedback by Type II and Type Ia SNe. The model also includes metal-dependent cooling and a multiphase treatment for the gas component. We find that a simulation without SN energy feedback is not able to produce a well-formed, extended disk component of the kind observed. However, as we turn on our SN energy feedback model, the star formation of the galaxy is regulated and a larger fraction of gas can survive until later times without losing its angular momentum. This availability of gas with high angular momentum contributes to the formation of stars at recent epochs, giving rise to a well-defined disk component with specific angular momentum comparable to observed values for spirals. The simulated galaxy also contains two distinct spheroidal components, a bulge and a stellar halo which show different chemical properties and star formation histories.