The Chandra Deep Protocluster Survey: Point-Source Catalogs for a 400 ks
  Observation of the z = 3.09 Protocluster in SSA22
  We present X-ray point-source catalogs for a deep 400 ks Chandra ACIS-I
exposure of the SSA22 field. The observations are centred on a z = 3.09
protocluster, which is populated by Lyman break galaxies (LBGs), Lyalpha
emitters (LAEs), and extended Lyalpha-emitting blobs (LABs). The survey reaches
ultimate (3 count) sensitivity limits of 5.7 X 10^-17 and 3.0 X 10^-16 ergs
cm^-2 s^-1 for the 0.5-2 keV and 2-8 keV bands, respectively. These limits make
SSA22 the fourth deepest extragalactic Chandra survey yet conducted, and the
only one focused on a known high redshift structure. In total, we detect 297
X-ray point sources and identify one obvious bright extended X-ray source over
a ~330 arcmin^2 region. In addition to our X-ray catalogs, we provide all
available optical spectroscopic redshifts and near-infrared and mid-infrared
photometry available for our sources. The basic X-ray and infrared properties
of our Chandra sources indicate a variety of source types, although absorbed
active galactic nuclei (AGNs) appear to dominate. In total, we have identified
12 X-ray sources (either via optical spectroscopic redshifts or LAE selection)
at z =3.06-3.12 that are likely to be associated with the SSA22 protocluster.
These sources have X-ray and multiwavelength properties that suggest they are
powered by AGN with 0.5-8 keV luminosities in the range of 10^43-10^45 ergs
s^-1 We have analysed the AGN fraction of sources in the protocluster as a
function of local LAE source density and find suggestive evidence for a
correlation between AGN fraction and local LAE source density (at the 96 per
cent confidence level), implying that supermassive black hole growth at z = 3
is strongest in the highest density regions.
