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arXiv · 1109.5123

The Ultraviolet-to-Mid-Infrared Spectral Energy Distribution of Weak Emission Line Quasars

Ryan A. Lane·Ohad Shemmer·Aleksandar M. Diamond-Stanic·Xiaohui Fan·Scott F. Anderson·W. N. Brandt·Richard M. Plotkin·Gordon T. Richards·Donald P. Schneider·Michael A. Strauss
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Abstract

We present Spitzer Space Telescope photometry of 18 Sloan Digital Sky Survey (SDSS) quasars at 2.7 <= z <= 5.9 which have weak or undetectable high-ionization emission lines in their rest-frame ultraviolet (UV) spectra (hereafter weak-lined quasars, or WLQs). The Spitzer data are combined with SDSS spectra and ground-based, near-infrared (IR) photometry of these sources to produce a large inventory of spectral energy distributions (SEDs) of WLQs across the rest-frame ~0.1-5 mum spectral band. The SEDs of our sources are inconsistent with those of BL Lacertae objects which are dominated by synchrotron emission due to a jet aligned close to our line-of-sight, but are consistent with the SED of ordinary quasars with similar luminosities and redshifts that exhibit a near-to-mid-IR 'bump', characteristic of hot dust emission. This indicates that broad emission lines in WLQs are intrinsically weak, rather than suffering continuum dilution from a jet, and that such sources cannot be selected efficiently from traditional photometric surveys.

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Ryan A. Lane, Ohad Shemmer, Aleksandar M. Diamond-Stanic, Xiaohui Fan, Scott F. Anderson, W. N. Brandt, Richard M. Plotkin, Gordon T. Richards, Donald P. Schneider, Michael A. Strauss. 2011-09-23. The Ultraviolet-to-Mid-Infrared Spectral Energy Distribution of Weak Emission Line Quasars. https://doi.org/10.1088/0004-637x%2F743%2F2%2F163

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