Compact Sunyaev-Zeldovich `hole' in the Bullet Cluster
  We present 18~GHz observations of the Bullet cluster from the Australia
Telescope Compact Array; in particular, a high angular resolution measurement
of the substructure in Sunyaev-Zel'dovich Effect (SZE). We report the discovery
of a compact SZE `hole' in the galaxy cluster. The SZE hole does not correspond
to any bright feature in X-ray, optical or lensing maps; in general, the
relatively deeper SZE features appear to avoid the regions with the most
intense X-ray emission. These imply that the gas pressure distribution differs
significantly from the distributions in gas emission measure, galaxy and dark
matter distributions. This has implications for the gas physics and evolution
in the cluster merger event. SZE displaced from X-ray centres implies that
modeling cluster dynamics is non-trivial; our observations indicate that our
current lack of understanding cluster merger astrophysics may be a limitation
to modeling the cosmological distribution in SZE cluster counts and the cluster
SZE contribution to small-angle cosmic microwave background (CMB) anisotropy.
The SZE distribution in the western parts of the cluster are cospatial with the
radio halo indicative of a common origin for the hot and relativistic electrons
in the turbulent wake of the Bullet.
