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Extragalactic X-Ray Sources and Their Contribution to the Diffuse Background: Invited Paper

Published online by Cambridge University Press:  14 August 2015

G. Setti  and
L. Woltjer
G. Setti
Affiliation:
Laboratorio di Radioastronomia CNR, University of Bologna, Italy
L. Woltjer
Affiliation:
Dept. of Astronomy, Columbia University, New York, N.Y., U.S.A.

Abstract

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We present estimates of the integrated contribution of extragalactic sources to the diffuse X-ray background in the 2–10 keV energy interval. It appears that classes of objects already detected as X-ray sources easily account for at least 10% of the background. Quasistellar objects, and possibly Seyfert and radio galaxies might contribute a larger fraction of the background intensity.

We also suggest that several of the unidentified X-ray sources in the UHURU catalogue at high galactic latitudes may be bright QSO's as yet unknown. The detection of a larger number of QSO's in the X-ray band may allow a decisive test for the cosmological interpretation of the redshifts of QSO's.

Type
Part III: Extragalactic Sources
Information
Symposium - International Astronomical Union , Volume 55: X- and Gamma-Ray Astronomy , 1973 , pp. 208 - 211
Copyright
Copyright © Reidel 1973 

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