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X-ray sources and the diffuse background

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Abstract

Possible numbers of X-ray sources at various flux levels are considered and their contribution to the background evaluated. Our conclusions are: The mean spectrum of Quasi-Stellar Objects and the nuclei of Seyfert galaxies between optical and X-ray wavelengths is characterized by a spectral index well in excess of 1.0. These objects may make an important contribution to the soft X-ray background. Observations of Q.S.O. may allow a decisive test for the cosmological interpretation of the redshifts of the Q.S.O. With regard to galactic sources we find that few undetected sources of the Sgr-Sco type exist, that these sources are located in the immediate neighborhood of the galactic center and that they account for at least 80% of the total galactic source luminosity. However, many intrinsically much fainter galactic sources may exist.

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Author notes

  1. G. Setti

    Present address: Laboratorio di Radioastronomia, University of Bologna, Italy

Authors and Affiliations

  1. Dept. of Astronomy, Columbia University, New York, N.Y., USA

    G. Setti & L. Woltjer

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  1. G. Setti
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  2. L. Woltjer
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Setti, G., Woltjer, L. X-ray sources and the diffuse background. Astrophys Space Sci 9, 185–192 (1970). https://doi.org/10.1007/BF00649964

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  • DOI: https://doi.org/10.1007/BF00649964

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