The MaGICC volume: reproducing statistical properties of high-redshift galaxies

Abstract

We present a cosmological hydrodynamical simulation of a representative volume of the Universe, as part of the Making Galaxies in a Cosmological Context (MaGICC) project. MaGICC uses a thermal implementation for supernova and early stellar feedback. This work tests the feedback model at lower resolution across a range of galaxy masses, morphologies and merger histories. The simulated sample compares well with observations of high redshift galaxies ($z \ge 2$) including the stellar mass - halo mass ($M_\star - M_h$ ) relation, the Galaxy Stellar Mass Function (GSMF) at low masses ($M_\star \lt 5 \times 10^{10} M_\odot$ ) and the number density evolution of low mass galaxies. The poor match of $M_\star - M_h$ and the GSMF at high masses ($M_\star \ge 5 \times 10^{10} M_\odot$ ) indicates supernova feedback is insufficient to limit star formation in these haloes. At $z = 0$, our model produces too many stars in massive galaxies and slightly underpredicts the stellar mass around $L_\star$ mass galaxy. Altogether our results suggest that early stellar feedback, in conjunction with supernovae feedback, plays a major role in regulating the properties of low mass galaxies at high redshift.