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arXiv · 1203.4521

Spectral energy distributions of quasars selected in the mid-infrared

Mark Lacy·Anna Sajina·Susan E. Ridgway·Danielle M. Nielsen·Tanya Urrutia·Duncan Farrah·Elinor L. Gates
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Abstract

We present preliminary results on fitting of SEDs to 142 z>1 quasars selected in the mid-infrared. Our quasar selection finds objects ranging in extinction from highly obscured, type-2 quasars, through more lightly reddened type-1 quasars and normal type-1s. We find a weak tendency for the objects with the highest far-infrared emission to be obscured quasars, but no bulk systematic offset between the far-infrared properties of dusty and normal quasars as might be expected in the most naive evolutionary schemes. The hosts of the type-2 quasars have stellar masses comparable to those of radio galaxies at similar redshifts. Many of the type-1s, and possibly one of the type-2s require a very hot dust component in addition to the normal torus emission.

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Mark Lacy, Anna Sajina, Susan E. Ridgway, Danielle M. Nielsen, Tanya Urrutia, Duncan Farrah, Elinor L. Gates. 2012-03-20. Spectral energy distributions of quasars selected in the mid-infrared. https://doi.org/10.1017/s1743921312009106

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