Mapping Incoherent Gravitational Wave Backgrounds
  Given the recent detection of gravitational waves from individual sources it
is almost a certainty that some form of background of gravitational waves will
be detected in future. The most promising candidate for such a detection are
backgrounds made up of incoherent superposition of the signal of unresolved
astrophysical or, backgrounds sourced by earlier cosmological events. Such
backgrounds will also contain anisotropies about an average value. The
information contained in the background level and any anisotropies will be
extremely valuable as an astrophysical and cosmological probe. As such, the
ability to reconstruct sky maps of the signal will become important as the
sensitivity increases. We build and test a pixel--based, maximum--likelihood
Gravitational Wave Background (GWB) map-maker that uses the cross-correlation
of sets of generalised baselines as input. The resulting maps are a
representation of the GWB power, or strain "intensity" on the sky. We test the
algorithm by reconstructing known input maps with different baseline
configurations. We also apply the map-maker to a subset of the Advance LIGO
data.
