A profile in FIRE: resolving the radial distributions of satellite galaxies in the Local Group with simulations

Understand

While many tensions between Local Group (LG) satellite galaxies and LCDM cosmology have been alleviated through recent cosmological simulations, the spatial distribution of satellites remains an important test of physical models and physical versus numerical disruption in simulations.

• Using the FIRE-2 cosmological zoom-in baryonic simulations, we examine the radial distributions of satellites with Mstar > 10^5 Msun around 8 isolated Milky Way- (MW) mass host galaxies and 4 hosts in LG-like pairs.
• We demonstrate that these simulations resolve the survival and physical destruction of satellites with Mstar >~ 10^5 Msun.
• The simulations broadly agree with LG observations, spanning the radial profiles around the MW and M31.