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arXiv · 1703.06888

Eddington-Limited Accretion in z~2 WISE-selected Hot, Dust-Obscured Galaxies

Jingwen Wu·Hyunsung D. Jun·Roberto J. Assef·Chao-Wei Tsai·Edward L. Wright·Peter R. M. Eisenhardt·Andrew Blain·Daniel Stern·Tanio Díaz-Santos·Kelly D. Denney·Brian T. Hayden·Saul Perlmutter·Greg Aldering·Kyle Boone·Parker Fagrelius
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Abstract

Hot, Dust-Obscured Galaxies, or "Hot DOGs", are a rare, dusty, hyperluminous galaxy population discovered by the WISE mission. Predominantly at redshifts 2-3, they include the most luminous known galaxies in the universe. Their high luminosities likely come from accretion onto highly obscured super massive black holes (SMBHs). We have conducted a pilot survey to measure the SMBH masses of five z~2 Hot DOGs via broad H_alpha emission lines, using Keck/MOSFIRE and Gemini/FLAMINGOS-2. We detect broad H_alpha emission in all five Hot DOGs. We find substantial corresponding SMBH masses for these Hot DOGs (~ 10^{9} M_sun), and their derived Eddington ratios are close to unity. These z~2 Hot DOGs are the most luminous AGNs at given BH masses, suggesting they are accreting at the maximum rates for their BHs. A similar property is found for known z~6 quasars. Our results are consistent with scenarios in which Hot DOGs represent a transitional, high-accretion phase between obscured and unobscured quasars. Hot DOGs may mark a special evolutionary stage before the red quasar and optical quasar phases, and they may be present at other cosmic epochs.

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Jingwen Wu, Hyunsung D. Jun, Roberto J. Assef, Chao-Wei Tsai, Edward L. Wright, Peter R. M. Eisenhardt, Andrew Blain, Daniel Stern, Tanio Díaz-Santos, Kelly D. Denney, Brian T. Hayden, Saul Perlmutter, Greg Aldering, Kyle Boone, Parker Fagrelius. 2017-03-20. Eddington-Limited Accretion in z~2 WISE-selected Hot, Dust-Obscured Galaxies. https://doi.org/10.3847/1538-4357%2Faa9ff3

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