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. This agreement does not
depend strongly on satellite mass, even at distances <~ 100 kpc. Host-to-host
variation dominates the scatter in satellite counts within 300 kpc of the
hosts, while time variation dominates scatter within 50 kpc. More massive host
galaxies within our sample have fewer satellites at small distances, likely
because of enhanced tidal destruction of satellites via the baryonic disks of
host galaxies. Furthermore, we quantify and provide fits to the tidal depletion
of subhalos in baryonic relative to dark matter-only simulations as a function
of distance. Our simulated profiles imply observational incompleteness in the
LG even at Mstar >~ 10^5 Msun: we predict 2-10 such satellites to be discovered
around the MW and possibly 6-9 around M31. To provide cosmological context, we
compare our results with the radial profiles of satellites around MW analogs in
the SAGA survey, finding that our simulations are broadly consistent with most
SAGA systems.Comment: 18 pages, 10 figures, plus appendices. Main results in figures 2, 3,
and 4. Accepted versio
