ON THE LARGE-SCALE STRUCTURE OF X-RAY-BACKGROUND SOURCES

The large scale clustering of the sources responsible for the X-ray background is discussed, under the assumption of a discrete origin. We develop the formalism necessary for calculating the X-ray spatial fluctuations in the most general case where the source density contrast in structures varies with redshift. A comparison of this with observational limits is useful for obtaining information concerning various galaxy formation scenarios. The calculations presented here show that a varying density contrast has a small impact on the expected X-ray fluctuations. This strengthens and extends our previous conclusions concerning the size and comoving density of large scale structures at redshifts 0.5 less-than-or-similar-to z less-than-or-similar-to 4.0.