The luminosity function of diverse satellite galaxy systems
  The high-resolution, SPH galaxies of the McMaster Unbiased Galaxy Survey
(MUGS) are used to examine the satellite systems of sixteen model host
galaxies. Each galaxy has a different mass, angular momentum and merger history
that yield a rich set of satellite luminosity functions. With new observations
of distant satellite systems, we can compare these luminosity functions to
satellite systems beyond the Local Group. We find that the luminosity functions
of our simulations compare well to observations when the luminosity functions
are scaled according to host mass. We use the recently-found relationship
between dwarf satellites and host mass in distant satellite systems (Trentham &
Tully 2009) to normalize a theoretical, complete luminosity function for the
Milky Way (Koposov et al. 2008). The luminosity function of satellites,
expressed as a function of the host mass, is given by dN/dM_V= 3.5 x
M_host^(0.91) x 10^(0.1 x M_V-10.2), where host mass is given in M_sun. The
mass of a host galaxy can be used to predict the number of dwarf satellites and
even when considering spiral and elliptical hosts separately this relation
holds.
