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Constraint on Quasar Number Counts from Their Contribution to The X-Ray Background

Published online by Cambridge University Press:  30 March 2016

J. P. Henry ,
A. Soltan ,
H. Tananbaum  and
G. Zamorani
J. P. Henry
Affiliation:
Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts, USA.
A. Soltan
Affiliation:
Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts, USA.
H. Tananbaum
Affiliation:
Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts, USA.
G. Zamorani
Affiliation:
Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts, USA.

Abstract

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Observations with the Einstein X-ray telescope show that quasars, as a class, are luminous X-ray emitters. By coupling our X-ray observations with quasar optical number counts, we can show that the quasars contribute significantly to the diffuse X-ray background. In fact, the X-ray data strongly suggest that somewhat above 20m the slope of the optical counts must flatten.

Type
Joint Discussion
Information
Highlights of Astronomy , Volume 5: Highlights of Astronomy. As presented at the XVIIth General Assembly of the IAU, 1979 , 1980 , pp. 771 - 774
Copyright
Copyright © Cambridge University Press 1980

References

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