I have mentioned previously Lusso (MPIA) and Hennawi's argument that there ought to be lots of obscured quasars: The unobscured quasars show hot dust emission indicating that there are lines of sight that pretty-much must be blocked. Today, Lusso and I tried to find some of these by messing with WISE data on BOSS LRGs. That is, we looked for galaxies with such prodigious mid-infrared output that there must be some other source (think: obscured AGN) powering it. We found a couple probable type-II (obscured) quasars and a lot of other random stuff, including wrong SDSS-III redshifts, blazars, and even a star in Orion (yes, mis-classified as a galaxy by the pipeline). Needles in haystacks: Still hard to find! That is, these obscured quasars should be plentiful, but hard to find in any simple data set.
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