2002/03/12 by O. Almaini, Almaini, O.
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysics (astro-ph) #Astrophysics and Cosmic Phenomena #FOS: Physical sciences #Galaxies: Formation, Evolution, Phenomena #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/0203173
4 pages, 2 figures. To appear in "A New Era in Cosmology", (ASP Conference Proceedings), eds. T. Shanks and N. Metcalfe
arxiv created 2002/03/12 · openalex publication_date 2002/03/12 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
It is becoming clear that luminous extragalactic X-ray and sub-mm sources are essentially distinct populations. Thus, if high redshift sub-mm sources represent massive spheroids in formation, there must be a time lag between the major epoch of star-formation and the appearance of a visible quasar. Despite this distinction, I find tentative evidence for a puzzling angular cross-correlation between X-ray sources and bright sub-mm sources in two independent fields. If this signal is due to large-scale structure it would argue for a low redshift (z<2) for many of the SCUBA sources. Alternatively, I suggest that the effect may be enhanced by gravitational lensing. The exceptionally steep slope of the bright sub-mm counts makes this population particularly prone to lensing bias. An apparent correlation may therefore be produced if X-ray sources trace the intervening large scale structure.