Hostname: page-component-586b7cd67f-t7czq Total loading time: 0 Render date: 2024-11-29T15:30:05.875Z Has data issue: false hasContentIssue false
  • English
  • Français

The X-ray properties of high redshift quasi-stellar objects

Published online by Cambridge University Press:  19 July 2016

Scott F. Anderson  and
Bruce Margon
Scott F. Anderson
Affiliation:
Department of Astronomy, FM-20, University of Washington, Seattle, Washington 98195, USA
Bruce Margon
Affiliation:
Department of Astronomy, FM-20, University of Washington, Seattle, Washington 98195, USA

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

We describe a program aimed at characterizing the X-ray emission of high redshift QSOs. We have obtained slitless spectra of 50 high galactic latitude fields previously imaged at very high levels of sensitivity by the Einstein Observatory, generally for original goals unrelated to QSOs. Our survey, covering ∼ 17 deg2 of sky to limiting magnitude Bcont ∼ 21, has yielded ∼ 400 previously uncatalogued QSO candidates, each with sensitive new X-ray information available. About 100 of these objects, constituting a “high confidence” set of QSOs, chiefly in the redshift range 1.7 < z < 3 and thus complementary to previous samples with X-ray data, are used to derive the X-ray properties of high redshift QSOs. Even at these most sensitive available X-ray flux levels, only about 25% of the objects are positively detected in X-rays; thus extensive attention has been given to proper treatment of the upper-limit information. We find a mean optical-to-X-ray slope parameter for the sample of . Our results are combined with those of previous surveys to estimate the fraction of the diffuse X-ray background radiation due to QSOs. QSOs are capable of supplying the majority of the radiation, but the chief contribution comes from an annulus of intermediate redshift, moderate luminosity objects.

Type
II. Continuum Emission
Information
Symposium - International Astronomical Union , Volume 119: Quasars , 1986 , pp. 247 - 252
Copyright
Copyright © Reidel 1986 

References

Anderson, S. F. 1985, , University of Washington.Google Scholar
Avni, Y., Soltan, A., Tananbaum, H., Zamorani, G. 1980, Ap. J., 238, 800.CrossRefGoogle Scholar
Avni, Y., and Tananbaum, H. 1982, Ap. J. (Letters), 262, L17.CrossRefGoogle Scholar
Caillault, J.-P., and Helfand, D. J. 1985, Ap. J., 289, 279.Google Scholar
Chanan, G. A. 1983, Ap. J., 275, 45.CrossRefGoogle Scholar
Elvis, M., and Lawrence, A., 1985, in “Astrophysics of Active Galaxies and Quasars”, Proc. 7th Santa Cruz Workshop on Astr. and Ap., Miller, J. (ed.).Google Scholar
Feigelson, E. D., and Nelson, P. I. 1985, Ap. J., 293, 192.Google Scholar
Giacconi, R., et al. 1979, Ap. J. (Letters), 234, L1.Google Scholar
Gioia, I. M., et al. 1984, Ap. J., 283, 495.Google Scholar
Margon, B., Downes, R. A., and Chanan, G. A. 1985, Ap. J. Suppl., 59, 23.Google Scholar
Marshall, H. L., et al. 1984, Ap. J., 283, 50.Google Scholar
Schmitt, J. H. M. M. 1985, Ap. J., 293, 178.CrossRefGoogle Scholar
Tananbaum, H. et al. 1979, Ap. J. (Letters), 234, L9.CrossRefGoogle Scholar
Veron, P. 1983, in “Quasars and Gravitational Lenses”, Proc. 24th Liège Int. Ap. Colloq., (Université de Liège), p. 210.Google Scholar
Zamorani, G. et al. 1981, Ap. J., 245, 357.Google Scholar