2000/07/14 by R. Gilli, Gilli, R.
Engineering · Physics and Astronomy · #Astronomical Observations and Instrumentation #Astronomy and Astrophysical Research #Astrophysics (astro-ph) #FOS: Physical sciences #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/0007207
3 pages, 2 figures, to appear in the Proceedings of the 4th Italian Conference on AGNs, Mem SAIt
arxiv created 2000/07/14 · openalex publication_date 2000/07/14 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
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.