Exotic sources detected in the 1 Ms Chandra Deep Field North Survey
Abstract
We provide constraints on optically faint (I>=24) X-ray sources, z>6 AGN, Very Red Objects (VROs; I-K>=4), and optically faint radio sources using the 1 Ms Chandra Deep Field North survey. We argue that the majority of the optically faint X-ray sources are obscured AGN at z=1-3. These sources comprise up to 50% of the X-ray detected AGN. Approximately 30% of the optically faint X-ray sources have properties consistent with those expected for z>6 AGN; however we argue that the majority of these sources lie at lower redshifts. The constraint we place on the source density of z>6 AGN (<~0.09 arcmin^{-2}) is below that predicted by some models. Approximately 30% of the optically faint X-ray sources are also VROs. Within the K<=20.1 VRO population, ~15% of the sources are AGN dominated. Conversely, we present evidence suggesting that non-AGN dominated VROs are detected at the flux limit of this 1 Ms Chandra survey. Finally, we show that ~50% of the optically faint radio source population are detected with X-ray emission. The majority of these sources appear to be obscured AGN.
- Publication:
-
arXiv e-prints
- Pub Date:
- February 2002
- DOI:
- 10.48550/arXiv.astro-ph/0202044
- arXiv:
- arXiv:astro-ph/0202044
- Bibcode:
- 2002astro.ph..2044A
- Keywords:
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- Astrophysics
- E-Print:
- 8 pages, 7 colour figures. Oral contribution to "New Visions of the X-ray Universe in the XMM-Newton and Chandra Era" 26-30 November 2001, ESTEC, The Netherlands. Includes required VisionStyle.cls