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HEAO A-2 soft X-ray source catalogThe HEAO A-2 low energy X-ray detectors have surveyed over 95% of the sky in the spectral bands 0.18-0.44 and 0.44-2.8 keV, down to a typical limiting sensitivity of 1 x 10 to the -11th and 3 x 10 to the -11th ergs per sq cm per sec in each band, respectively. Using a significance criterion of 6 sigma for existence, 114 sources are cataloged, of which 54 were previously undiscovered and 32 remain unidentified. The catalog contains a listing of all counterpart identifications and a cross-reference to all HEAO 1 A-2 low energy detector team publications on the catalog sources complete through the end of 1981. Supplementary material allows the estimation of spectral parameters for the spectral models from the observed intensities. Simple graphs allow the extraction of energy fluxes at the earth, both with and without the effects of interstellar absorption. The angular distribution of the cataloged sources in the 0.44-2.8 keV band is concentrated toward the galactic plane and resembles that seen at higher energy. The distribution in the 0.18-0.44 keV band is more uniform and contains many more newly discovered and unidentified sources.
Document ID
19830038858
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Nugent, J. J.
(California Inst. of Tech. Pasadena, CA, United States)
Jensen, K. A.
(California Institute of Technology Pasadena, CA, United States)
Nousek, J. A.
(California Inst. of Tech. Pasadena, CA, United States)
Garmire, G. P.
(Pennsylvania State University University Park, PA, United States)
Mason, K. O.
(California Inst. of Tech. Pasadena, CA, United States)
Walter, F. M.
(California Inst. of Tech. Pasadena, CA, United States)
Bowyer, C. S.
(California, University Berkeley, CA, United States)
Date Acquired
August 11, 2013
Publication Date
January 1, 1983
Publication Information
Publication: Astrophysical Journal Supplement Series
Volume: 51
Subject Category
Astronomy
Accession Number
83A20076
Funding Number(s)
CONTRACT_GRANT: NAS5-25049
Distribution Limits
Public
Copyright
Other

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