Sub-mm detection of a high redshift Type 2 QSO
Abstract
We report on the first SCUBA detection of a Type 2 QSO at z=3.660 in the Chandra Deep Field South. This source is X-ray absorbed, shows only narrow emission lines in the optical spectrum and is detected in the sub-mm: it is the ideal candidate in an evolution scheme for AGN (e.g. Fabian (1999); Page et al. (2004)) of an early phase corresponding to the main growth of the host galaxy and formation of the central black hole. The overall photometry (from the radio to the X-ray energy band) of this source is well reproduced by the spectral energy distribution (SED) of NGC 6240, while it is incompatible with the spectrum of a Type 1 QSO (3C273) or a starburst galaxy (Arp 220). Its sub-mm (850 \mu m) to X-ray (2 keV) spectral slope (alpha_SX) is close to the predicted value for a Compton-thick AGN in which only 1% of the nuclear emission emerges through scattering. Using the observed flux at 850 \mu m we have derived a SFR=550--680 M_dust=4.2 10^8 M_odot
Cite
@article{arxiv.astro-ph/0410632,
title = {Sub-mm detection of a high redshift Type 2 QSO},
author = {V. Mainieri and D. Rigopoulou and I. Lehmann and S. Scott and I. Matute and O. Almaini and P. Tozzi and G. Hasinger and J. S. Dunlop},
journal= {arXiv preprint arXiv:astro-ph/0410632},
year = {2009}
}
Comments
6 Pages, 5 Figures, accepted for publication in MNRAS