Abstract / Description of output
We present a large X-ray selected serendipitous cluster survey based on
a novel joint analysis of archival Chandra and XMM-Newton data. The
survey provides enough depth to reach clusters of flux of
10-14 ergs cm-2 s-1 near z 1 and
simultaneously a large enough sample to find evidence for the strong
evolution of clusters expected from structure formation theory. We
detected a total of 723 clusters of which 462 are newly discovered
clusters with greater than 6 significance. In addition, we also detect
and measure 261 previously-known clusters and groups that can be used to
calibrate the survey. The survey exploits a technique which combines the
exquisite Chandra imaging quality with
the high throughput of the XMM Newton telescopes using overlapping
survey regions. A large fraction of the contamination from AGN point
sources is mitigated by using this technique. This results in a higher
sensitivity for finding clusters of galaxies with relatively few photons
and a large part of our survey has a flux sensitivity between
10-14 and 10-15 ergs cm2 s-1. The survey covers
41.2 square degrees of overlapping Chandra and XMM Newton fields and
122.2 square degrees of non-overlapping Chandra data. We measure the log
N-log S distribution and fit it with a redshift-dependent model
characterized by a luminosity distribution proportional to
e-z/z0. We find that z0 to be in the range 0.7 to 1.3,
indicative of rapid cluster evolution, as expected for cosmic structure
formation using parameters appropriate to the concordance cosmological
model. With a combination of SDSS, UKIDSS, and pointed optical follow-up
observations, we are measuring the false detection rate and estimating
photometric redshifts. This will enable precision measurements of
cosmological parameters by using the evolution of the cluster mass
function.
Original language | English |
---|---|
Pages (from-to) | 21301 |
Journal | Bulletin of the American Astronomical Society |
Volume | 43 |
Publication status | Published - 1 Jan 2011 |
Event | American Astronomical Society 217th Meeting - Seattle, Washington, United States Duration: 9 Jan 2011 → 13 Jan 2011 |