2002/09/19 by C. Vignali, D. M. Alexander, Vignali, C. +11
Engineering · Physics and Astronomy · #Astronomical Observations and Instrumentation #Astronomy and Astrophysical Research #Astrophysical Phenomena and Observations #Astrophysics (astro-ph) #FOS: Physical sciences #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/0209415
4 pages, 4 figures, Latex macro sprocl.sty, to be published in the proceedings of the 5th Italian AGN Meeting "Inflows, Outflows and Reprocessing around black holes" (2002)
arxiv created 2002/09/19 · openalex publication_date 2002/09/19 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Understanding the nature of Extremely Red Objects [EROs; (I-K)>=4] is one of the most challenging issues in observational cosmology. Here we report on the X-ray constraints provided by the 2 Ms Chandra Deep Field-North Survey (CDF-N). X-ray emission has been detected from 11 out of 36 EROs (approx 30%). Five of these have hard X-ray emission and appear to be obscured AGNs, while non-AGN emission (star formation or normal elliptical galaxy emission) is likely to be the dominant source of X-rays from the soft X-ray sources detected at the faintest X-ray flux levels.