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SwiftAGN&ClusterSurvey(SACS)Soft-Band(0.5-2keV)PointSourceCatalog

Metadata Updated: September 19, 2025

The Swift Active galactic nucleus (AGN) and Cluster Survey (SACS) uses 125 deg<sup>2</sup> of Swift X-ray Telescope (XRT) serendipitous fields with variable depths surrounding gamma-ray bursts to provide a medium depth (4 x 10<sup>-15</sup> erg cm<sup>-2</sup> s<sup>-1</sup>) and medium area survey filling the gap between deep, narrow Chandra/XMM-Newton surveys and wide, shallow ROSAT surveys. In the reference paper, a catalog of 22,563 point sources and 442 extended sources, and the number counts of the AGN and galaxy cluster populations are presented. SACS provides excellent constraints on the AGN number counts at the bright end with negligible uncertainties due to cosmic variance, and these constraints are consistent with previous measurements. The authors use Wide-field Infrared Survey Explorer (WISE) mid-infrared(MIR) colors to classify the sources. For AGNs, they can roughly separate the point sources into MIR-red and MIR-blue AGNs, finding roughly equal numbers of each type in the soft X-ray band (0.5-2.0 keV), but fewer MIR-blue sources in the hard X-ray band (2-8 keV). The cluster number counts, with 5% uncertainties from cosmic variance, are also consistent with previous surveys but span a much larger continuous flux range. Deep optical or IR followup observations of this cluster sample will significantly increase the number of higher redshift (z > 0.5) X-ray-selected clusters. This HEASARC table contains the list of 17,748 Swift XRT point sources which were detected in the soft X-ray band image (0.5-2.0 keV) using wavdetect with a false positive threshold of 10<sup>-6</sup> (contained in Table 2 of the reference paper). The authors consider these sources to be AGN candidates. This table was created by the HEASARC in June 2015 based on an electronic version of Table 2 of the reference paper, the list of Swift XRT point sources detected in the soft X-ray (0.5-2 keV) band, which was obtained from the ApJS web site. This is a service provided by NASA HEASARC .

Access & Use Information

Public: This dataset is intended for public access and use. License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

Downloads & Resources

Dates

Metadata Created Date April 11, 2025
Metadata Updated Date September 19, 2025

Metadata Source

Harvested from NASA Data.json

Additional Metadata

Resource Type Dataset
Metadata Created Date April 11, 2025
Metadata Updated Date September 19, 2025
Publisher High Energy Astrophysics Science Archive Research Center
Maintainer
Identifier ivo://nasa.heasarc/sacsspscat
Data Last Modified 2025-09-10
Category Astrophysics
Public Access Level public
Bureau Code 026:00
Metadata Context https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
Schema Version https://project-open-data.cio.gov/v1.1/schema
Catalog Describedby https://project-open-data.cio.gov/v1.1/schema/catalog.json
Harvest Object Id f9f728c1-1d21-4f49-bbaf-1f54f7b2f497
Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
Harvest Source Title NASA Data.json
Homepage URL https://heasarc.gsfc.nasa.gov/W3Browse/all/sacsspscat.html
Program Code 026:000
Source Datajson Identifier True
Source Hash 31da467a85d4d0b075ae039af51b4182588375a94c79eb84163bd6e554126153
Source Schema Version 1.1

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