Normalized to: He.
[1]
oai:arXiv.org:1105.0691 [pdf] - 1076394
Statistical Characterization of the Chandra Source Catalog
Primini, Francis A.;
Houck, John C.;
Davis, John E.;
Nowak, Michael A.;
Evans, Ian N.;
Glotfelty, Kenny J.;
Anderson, Craig S.;
Bonaventura, Nina R.;
Chen, Judy C.;
Doe, Stephen M.;
Evans, Janet D.;
Fabbiano, Giuseppina;
Galle, Elizabeth C.;
Gibbs, Danny G.;
Grier, John D.;
Hain, Roger M.;
Hall, Diane M.;
Harbo, Peter N.;
Xiangqun;
He;
Karovska, Margarita;
Kashyap, Vinay L.;
Lauer, Jennifer;
McCollough, Michael L.;
McDowell, Jonathan C.;
Miller, Joseph B.;
Mitschang, Arik W.;
Morgan, Douglas L.;
Mossman, Amy E.;
Nichols, Joy S.;
Plummer, David A.;
Refsdal, Brian L.;
Rots, Arnold H.;
Siemiginowska, Aneta;
Sundheim, Beth A.;
Tibbetts, Michael S.;
Van Stone, David W.;
Winkelman, Sherry L.;
Zografou, Panagoula
Submitted: 2011-05-03, last modified: 2011-05-05
The first release of the Chandra Source Catalog (CSC) contains ~95,000 X-ray
sources in a total area of ~0.75% of the entire sky, using data from ~3,900
separate ACIS observations of a multitude of different types of X-ray sources.
In order to maximize the scientific benefit of such a large, heterogeneous
data-set, careful characterization of the statistical properties of the
catalog, i.e., completeness, sensitivity, false source rate, and accuracy of
source properties, is required. Characterization efforts of other, large
Chandra catalogs, such as the ChaMP Point Source Catalog (Kim et al. 2007) or
the 2 Mega-second Deep Field Surveys (Alexander et al. 2003), while
informative, cannot serve this purpose, since the CSC analysis procedures are
significantly different and the range of allowable data is much less
restrictive. We describe here the characterization process for the CSC. This
process includes both a comparison of real CSC results with those of other,
deeper Chandra catalogs of the same targets and extensive simulations of
blank-sky and point source populations.
[
2]
oai:arXiv.org:1005.4665 [pdf] - 1032725
The Chandra Source Catalog
Evans, Ian N.;
Primini, Francis A.;
Glotfelty, Kenny J.;
Anderson, Craig S.;
Bonaventura, Nina R.;
Chen, Judy C.;
Davis, John E.;
Doe, Stephen M.;
Evans, Janet D.;
Fabbiano, Giuseppina;
Galle, Elizabeth C.;
Gibbs, Danny G.;
Grier, John D.;
Hain, Roger M.;
Hall, Diane M.;
Harbo, Peter N.;
Xiangqun;
He;
Houck, John C.;
Karovska, Margarita;
Kashyap, Vinay L.;
Lauer, Jennifer;
McCollough, Michael L.;
McDowell, Jonathan C.;
Miller, Joseph B.;
Mitschang, Arik W.;
Morgan, Douglas L.;
Mossman, Amy E.;
Nichols, Joy S.;
Nowak, Michael A.;
Plummer, David A.;
Refsdal, Brian L.;
Rots, Arnold H.;
Siemiginowska, Aneta;
Sundheim, Beth A.;
Tibbetts, Michael S.;
Van Stone, David W.;
Winkelman, Sherry L.;
Zografou, Panagoula
Submitted: 2010-05-25
The Chandra Source Catalog (CSC) is a general purpose virtual X-ray
astrophysics facility that provides access to a carefully selected set of
generally useful quantities for individual X-ray sources, and is designed to
satisfy the needs of a broad-based group of scientists, including those who may
be less familiar with astronomical data analysis in the X-ray regime. The first
release of the CSC includes information about 94,676 distinct X-ray sources
detected in a subset of public ACIS imaging observations from roughly the first
eight years of the Chandra mission. This release of the catalog includes point
and compact sources with observed spatial extents <~ 30''. The catalog (1)
provides access to the best estimates of the X-ray source properties for
detected sources, with good scientific fidelity, and directly supports
scientific analysis using the individual source data; (2) facilitates analysis
of a wide range of statistical properties for classes of X-ray sources; and (3)
provides efficient access to calibrated observational data and ancillary data
products for individual X-ray sources, so that users can perform detailed
further analysis using existing tools. The catalog includes real X-ray sources
detected with flux estimates that are at least 3 times their estimated 1 sigma
uncertainties in at least one energy band, while maintaining the number of
spurious sources at a level of <~ 1 false source per field for a 100 ks
observation. For each detected source, the CSC provides commonly tabulated
quantities, including source position, extent, multi-band fluxes, hardness
ratios, and variability statistics, derived from the observations in which the
source is detected. In addition to these traditional catalog elements, for each
X-ray source the CSC includes an extensive set of file-based data products that
can be manipulated interactively.