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Last modified: 21 July 2009

URL: http://cxc.harvard.edu/csc1/index.html

The Chandra Source Catalog

Release 1.0.1: Point and compact source catalog

[Chandra Source Catalog - sky coverage image in Galactic coordinates]
The locations of observations included in the CSC, in Galactic coordinates (click the image for equatorial coordinates).
The size of each symbol is proportional to the logarithm of the number of sources detected in the field,
while the color encodes the number of closely-located observations.

The Chandra Source Catalog (CSC) is ultimately intended to be the definitive catalog of X-ray sources detected by the Chandra X-ray Observatory. To achieve that goal, the catalog will be released to the user community in a series of increments with increasing capability. The first official release of the CSC includes information about sources detected in public ACIS imaging observations from roughly the first eight years of the Chandra mission. Only point sources, and compact sources, with observed spatial extents <~30 arcseconds, are included. Highly extended sources, and sources located in selected fields containing bright, highly extended sources, are excluded from the first release.

The CSC contains positions and multi-band count rates for the sources, as well as derived spatial, spectral, and temporal calibrated source properties that may be compared with data obtained by other telescopes. The CSC also includes associated data products for each source, including images, photon event lists, light curves, and spectra.

Each distinct source on the sky (i.e., object at a specific RA and Dec) is recorded in a single "master source" table entry and one or more "source observation" table entries. The individual source entries contain the properties of a single detection from a single observation. The master source entry is the best estimate of all the properties of a source, based on the data extracted from the individual source entries. The Catalog Organization page contains further details.

The current version of the catalog is release 1.0.1. This version fixes the var_flag error that was present in release 1.0 of the catalog.

The Schedule and Status page has the current processing status and release schedule.

Users are urged to review the catalog Caveats and Limitations prior to using the CSC for their scientific investigations.

Questions about the CSC may be submitted to the CXC Helpdesk; refer also to the FAQs section of the website for answers to frequently asked questions.

Request for Acknowledgment of Use of the Chandra Source Catalog

Users are kindly requested to acknowledge in the acknowledgment section of any resulting publications their use of the Chandra Source Catalog.

This will help us greatly to keep track of catalog usage, information that is essential for providing full accountability of our work and services, as well as for planning future services.

The following language is suggested:

This research has made use of data obtained from the Chandra Source Catalog, provided by the Chandra X-ray Center (CXC) as part of the Chandra Data Archive.

We would like to remind you that it is also very helpful for us if you could include Dataset Identifiers in the manuscript. The Dataset Identifier for the Chandra Source Catalog is:

ADS/Sa.CXO#CSC

Last modified: 21 July 2009


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