Diane M. Harnak Hall

STATISTICAL CHARACTERIZATION OF THE CHANDRA SOURCE CATALOG

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 ~3900 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 or the 2 Mega-second Deep Field Surveys, 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.

Tracking the processing status of Chandra observations

The Chandra Data Archive has been archiving and distributing data for the Chandra X-ray Observatory and keeping observers informed of the status of their observations since shortly after launch in July 1999. Due to the complicated processing history of Chandra data, it became apparent that a database was needed to track this history on an observation by observation basis. The result is the Processing Status Database and the Chandra Observations Processing Status tool. In this paper, a description of the database design is given, followed by details of the tools which populate and display the database.