CANDIDATE TYPE II QUASARS FROM THE SLOAN DIGITAL SKY SURVEY. I. SELECTION AND OPTICAL PROPERTIES OF A SAMPLE AT 0.3 < Z < 0.83

@article{Zakamska2003CANDIDATETI,
  title={CANDIDATE TYPE II QUASARS FROM THE SLOAN DIGITAL SKY SURVEY. I. SELECTION AND OPTICAL PROPERTIES OF A SAMPLE AT 0.3 < Z < 0.83},
  author={Nadia L. Zakamska and Michael A. Strauss and Julian H. Krolik and M.J.Collinge and P.B.Hall and L.Hao and T.M.Heckman and Z.Ivezic and G.T.Richards and D.J.Schlegel and D.P.Schneider and I.Strateva and Daniel E. vanden Berk and S.F.Anderson and Jon Brinkmann Johns Hopkins University and Johns Hopkins University},
  journal={The Astronomical Journal},
  year={2003},
  volume={126},
  pages={2125-2144}
}
Type II quasars are the long-sought luminous analogs of type 2 (narrow emission line) Seyfert galaxies, suggested by unification models of active galactic nuclei (AGNs) and postulated to account for an appreciable fraction of the cosmic hard X-ray background. We present a sample of 291 type II AGNs at redshifts 0.3 < Z < 0.83 from the spectroscopic data of the Sloan Digital Sky Survey. These objects have narrow (FWHM < 2000 km s-1), high equivalent width emission lines with high-ionization line… Expand
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