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N.L. Zakamska, M.A. Strauss, Z. Ivezic (Princeton University), G.D. Schmidt (University of Arizona), BLANK BLANK
The success of unification models for Seyfert galaxies raises the question of whether these models can be extended to high luminosity AGNs. Do obscured (type II) quasars exist? If so, how many are there? To date, only a small number of candidates have been found. We recently published a sample of 150 type II quasar candidates at redshifts z<0.8 selected by their emission line properties from the spectroscopic database of the Sloan Digital Sky Survey. We are conducting a multi-wavelength follow-up of this sample from radio wavelengths to X-rays using data from HST, Chandra, XMM, MMT and other telescopes. IRAS data show that far-infrared luminosities of objects in our sample are as high as 1047 erg sec-1, placing them among the most luminous quasars at low redshifts. Preliminary results suggest that type II quasars from our sample show a wide range of X-ray luminosities and obscuring column densities. Other exciting properties of the objects in our sample are irregular morphologies of many of the host galaxies and very high optical polarization of the nuclei. By studying type II quasars we are for the first time able to probe unification models at high luminosities. We will use the SDSS sample of type II quasars to determine the luminosity function of type II AGN, their fraction in the AGN population and the contribution of obscured AGN to the census of supermassive black holes.
Funding for the SDSS is provided by the Alfred P. Sloan Foundaton, NASA, NSF, DoE, Monbukagakusho, the Max Planck Society and the member institutions. The SDSS web site is http://www.sdss.org.
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Bulletin of the American Astronomical Society, 36 #2
© YEAR. The American Astronomical Soceity.