2012/05/11 by Ewald Puchwein, Volker Springel · 5 citations
Physics and Astronomy · #Active galactic nucleus #Astronomy #Astrophysics #Astrophysics and Star Formation Studies #Cosmology and Gravitation Theories #Galaxies: Formation, Evolution, Phenomena #Galaxy #Galaxy formation and evolution #Initial mass function #Physics #Redshift #Star formation #Stellar mass #Supernova #astro-ph.CO
paper · pdf · doi:10.1093/mnras/sts243
14 pages, 9 figures, submitted to MNRAS
arxiv created 2012/05/11 · openalex publication_date 2012/11/23 · arxiv updated 2015/06/05 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Cosmological hydrodynamical simulations of galaxy formation in representative regions of the Universe typically need to resort to subresolution models to follow some of the feedback processes crucial for galaxy formation. Here, we show that an energy-driven outflow model in which the wind velocity decreases and the wind mass loading increases in low-mass galaxies, as suggested by observations, can produce a good match to the low-mass end of the observed galaxy stellar mass function. The high-mass end can be recovered simultaneously if feedback from active galactic nuclei (AGN) and a correction for diffuse stellar light plausibly missed in observations are included. We find, however, that the resolution requirements for simulations including AGN feedback are more demanding than for wind feedback alone, making our highest resolution simulations with AGN and winds only marginally converged. Encouragingly, our model is in reasonable agreement with the observed stellar mass functions at redshifts z = 1 and z = 2, and the observed redshift evolution of the cosmic star formation rate density. In addition, at least in simulations without AGN, our wind model accurately reproduces the observed gas to stellar mass ratios and specific star formation rates of galaxies as a function of their stellar mass. This agreement with a diverse set of data marks significant progress in hydrodynamically modelling the formation of a representative galaxy population. It also suggests that the mass flux in real galactic winds should strongly increase towards low-mass galaxies. Without this assumption, an overproduction of galaxies at the faint-end of the galaxy luminosity function seems inevitable in our models.