Dissecting the Lyman Alpha Emission Halo of LAB1
  We report observations of Lyman Alpha Blob 1 (LAB1) in the SSA 22
protocluster region (z=3.09) with the integral-field spectrograph SAURON. We
increased the signal-to-noise in the spectra by more than a factor three
compared to our previous observations. This allows us to probe the structure of
the LAB system in detail, examining its structure in the spatial and wavelength
dimensions. We find that the emission from the system comes largely from five
distinct blobs. Two of the emission regions are associated with Lyman Break
Galaxies, while a third appears to be associated with a heavily obscured
submillimeter galaxy. The fourth and fifth components do not appear to be
associated with any galaxy despite the deep imaging that is available in this
field. If we interpret wavelength shifts in the line centroid as velocity
structure in the underlying gas, many of these emission systems show evidence
of velocity shear. It remains difficult to distinguish between an underlying
rotation of the gas and an outflow driven by the central object. We have
examined all of the line profiles for evidence of strong absorption features.
While several systems are better fitted by the inclusion of a weak absorption
component, we do not see evidence for a large-scale coherent absorption feature
such as that seen in LAB2.
