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Hyunsung Jun (JPL) -- Distant Quasars: Black hole mass growth and dust emission

March

I will report on the early evolution of active galactic nuclei (AGNs) through the growth of black hole (BH) mass and their dust emission strength. Using a sample of 155 luminous quasars at 3<z<6 observed with the AKARI, we measured BH masses from rest-frame optical spectra, extending the scaling relations between AGN continuum and line luminosities to luminous, high redshift quasars. We also investigated the BH mass estimator scaling relations of H-alpha, MgII, and CIV compared to the H-beta BH mass estimator. This work provides constraints on the massive end of BH mass growth at high redshift. Next, we identified and characterized a population of luminous dust-poor quasars at z<5 - quasars showing little IR emission from the AGN dusty structure. Compiling a rest-frame UV to IR library of 41,000 optically selected type-1 quasars, we fitted the broad-band spectral energy distributions (SEDs) with accretion disk and dust model components. We find that 0.6% of the sample is hot-dust-poor, and present their observed properties.

Date: March 4th, 2015

Location: MR LCR