2012ApJ...761..184W

Mid-infrared spectroscopic measurements from the Infrared Spectrometer (IRS) on Spitzer are given for 125 hard X-ray active galactic nuclei (AGNs; 14-195 keV) from the Swift Burst Alert Telescope (BAT) sample and for 32 AGNs with black hole masses (BHMs) from reverberation mapping. The 9.7 µm silicate feature in emission or absorption defines an infrared AGN classification describing whether AGNs are observed through dust clouds, indicating that 55% of the BAT AGNs are observed through dust. The mid-infrared dust continuum luminosity is shown to be an excellent indicator of intrinsic AGN luminosity, scaling closely with the hard X-ray luminosity, log νL_ν(7.8 µm)/L(X) = -0.31±0.35, and independent of classification determined from silicate emission or absorption. Dust luminosity scales closely with BHM, log νL _ν(7.8 µm) = (37.2±0.5) + 0.87 log BHM for luminosity in erg/s and BHM in M_☉. The 100 most luminous type 1 quasars as measured in νL_ν(7.8 µm) are found by comparing Sloan Digital Sky Survey (SDSS) optically discovered quasars with photometry at 22 µm from the Wide-Field Infrared Survey Explorer (WISE), scaled to rest frame 7.8 µm using an empirical template determined from IRS spectra. The most luminous SDSS/WISE quasars have the same maximum infrared luminosities for all 1.5 < z < 5, reaching total infrared luminosity L_IR= 10^14.4 L_☉. Comparing with dust-obscured galaxies from Spitzer and WISE surveys, we find no evidence of hyperluminous obscured quasars whose maximum infrared luminosities exceed the maximum infrared luminosities of optically discovered quasars. Bolometric luminosities L_bol estimated from rest-frame optical or ultraviolet luminosities are compared to L_IR. For the local AGN, the median log L _IR/L_bol= -0.35, consistent with a covering factor of 45% for the absorbing dust clouds. For the SDSS/WISE quasars, the median log L_IR/L_bol= 0.1, with extremes indicating that ultraviolet-derived L_bol can be seriously underestimated even for type 1 quasars.