We discuss a simple model for the cosmic X-ray background (XRB), based on the unified Seyfert scheme. We show that a mixture of unabsorbed type 1 and absorbed type 2 Seyferts, integrated in redshift back to z = 3.5, can simultaneously reproduce the spectrum of the XRB from 1 to 150 keV and the source counts in both the soft and hard X-ray bands. The presence of numerous, heavily obscured sources with hard spectra at a flux level of 10-12 erg cm-2 s-1 is indicated as a test of the model, in view of forthcoming ASCA observations.
Madau, P., Ghisellini, G., Fabian, A. (1994). The unified Seyfert scheme and the origin of the cosmic X-ray background. MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 270(1), 17-21 [10.1093/mnras/270.1.L17].
The unified Seyfert scheme and the origin of the cosmic X-ray background
Madau, P;
1994
Abstract
We discuss a simple model for the cosmic X-ray background (XRB), based on the unified Seyfert scheme. We show that a mixture of unabsorbed type 1 and absorbed type 2 Seyferts, integrated in redshift back to z = 3.5, can simultaneously reproduce the spectrum of the XRB from 1 to 150 keV and the source counts in both the soft and hard X-ray bands. The presence of numerous, heavily obscured sources with hard spectra at a flux level of 10-12 erg cm-2 s-1 is indicated as a test of the model, in view of forthcoming ASCA observations.
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