X-ray Background Constraints on the Log N–Log S Relation for AGN
نویسندگان
چکیده
منابع مشابه
Testing the Agn Models for the X-ray Background
We will briefly examine the following three issues related to the AGN synthesis models for X-ray background: 1) the possibility that absorbed AGNs evolve faster than unabsorbed ones; 2) the existence of the still debated population of luminous absorbed AGNs, the so-called QSO2s; 3) the behavior of the AGN density at a redshift above ∼ 3.
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We discuss the relationship between rest-frame color and optical luminosity for X-ray sources in the range 0.6 < z < 1.4 selected from the Chandra survey of the Extended Groth Strip (EGS). These objects are almost exclusively active galactic nuclei (AGN). While there are a few luminous QSOs, most are relatively weak or obscured AGN whose optical colors should be dominated by host galaxy light. ...
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We discuss the constraints on the AGN evolution from the cosmic X–ray background and source counts. A synthesis model to fit the X–ray background is presented. The data used are a compilation from Gruber (1992), mainly based on HEAO-1 data. The spectrum of type 2 AGN has been modeled including Compton down– scattering within the absorbing material. We found an improvement when a dependence on r...
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ژورنال
عنوان ژورنال: Symposium - International Astronomical Union
سال: 1989
ISSN: 0074-1809
DOI: 10.1017/s0074180900140859