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ChandraLockmanAreaNorthSurvey(CLANS)Optical&IRCatalog

Metadata Updated: January 16, 2026

This table contains the redshift catalog for the X-ray sources detected in the Chandra Lockman Area North Survey (CLANS). The redshifts for the CLANS field are all new. For fluxes above 10<sup>-14</sup> ergs cm<sup>-2</sup> s<sup>-1</sup> (2-8 keV) the authors have redshifts for 76% of the sources in the CLANS, CLASXS, and CDF-N surveys. They extend the redshift information for the full sample using photometric redshifts. The goal of the OPTX Project is to use these three surveys, which are among the most spectroscopically complete surveys to date, to analyze the effect of spectral type on the shape and evolution of the X-ray luminosity functions and to compare the optical spectral types with the X-ray spectral properties. The optical and infrared photometric catalog for the CLANS X-ray sources is presented here (see the CLANS Browse table for the X-ray information). The CLANS and CLASXS surveys bridge the gap between the ultra-deep pencil-beam surveys, such as the CDFs, and the shallower, very large-area surveys. As a result, they probe the X-ray sources that contribute the bulk of the 2-8 keV X-ray background and cover the flux range of the observed break in the log N - log S distribution. This table was created by the HEASARC in December 2008 based on the electronic version of Table 11 from the paper which was obtained from the ApJ 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 January 16, 2026

Metadata Source

Harvested from NASA Data.json

Additional Metadata

Resource Type Dataset
Metadata Created Date April 11, 2025
Metadata Updated Date January 16, 2026
Publisher High Energy Astrophysics Science Archive Research Center
Maintainer
Identifier ivo://nasa.heasarc/clansoid
Data Last Modified 2026-01-13
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 21b139ef-e4ed-43a3-96d3-89364a33607a
Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
Harvest Source Title NASA Data.json
Homepage URL https://heasarc.gsfc.nasa.gov/W3Browse/all/clansoid.html
Program Code 026:000
Source Datajson Identifier True
Source Hash 66e523a28881ae4c87c63dbfe50ad93f24037c9044b94ce635e5aeec7287caa0
Source Schema Version 1.1

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