Isolating the Foreground of the X-Ray Background
نویسنده
چکیده
The foreground component of the X-ray Background (XRB) can be studied by cross-correlating its intensity with galaxy catalogs. We computed the two-point cross-correlation function W xg between 67 Einstein X-ray elds and the APM galaxy catalog. We detected a signal with an amplitude of W xg = :04 :01, signi cant at the 3:5 level. The reality of this signal was tested with a series of control data sets. We discuss how this signal can be used to constrain models of the XRB.
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