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At low redshifts, dust-obscured quasars often have strong yet narrowpermitted lines in the rest-frame optical and ultraviolet, excited by thecentral active nucleus, earning the designation Type II quasars. We present asample of 145 candidate Type II quasars at redshifts between 2 and 4.3,encompassing the epoch at which quasar activity peaked in the universe. Theseobjects, selected from the quasar sample of the Baryon OscillationSpectroscopic Survey of the Sloan Digital Sky Survey III, are characterized byweak continuum in the rest-frame ultraviolet (typical continuum magnitude of i\approx 22) and strong lines of CIV and Ly \alpha, with Full Width at HalfMaximum less than 2000 kms-1. The continuum magnitudes correspond to anabsolute magnitude of -23 or brighter at redshift 3, too bright to be dueexclusively to the host galaxies of these objects. Roughly one third of theobjects are detected in the shorter-wavelength bands of the WISE survey; thespectral energy distributions (SEDs) of these objects appear to be intermediatebetween classic Type I and Type II quasars seen at lower redshift. Five objectsare detected at rest frame 6\mu m by Spitzer, implying bolometric luminositiesof several times 10^46 erg s-1. We have obtained polarization measurements fortwo objects; they are roughly 3% polarized. We suggest that these objects areluminous quasars, with modest dust extinction (A_V ~ 0.5 mag), whoseultraviolet continuum also includes a substantial scattering contribution.Alternatively, the line of sight to the central engines of these objects may bepartially obscured by optically thick material.

Candidate Type II Quasars at 2 < z < 4.3 in the Sloan Digital Sky Survey III