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arXiv · 1509.00342

Radio Jet Feedback and Star Formation in Heavily Obscured Quasars at Redshifts ~0.3-3, I: ALMA Observations

Carol J. Lonsdale·Mark Lacy·Amy E. Kimball·Andrew Blain·Mark Whittle·Belinda Wilkes·Dan Stern·Jim Condon·Minjin Kim·Roberto J. Assef·Chao-Wei Tsai·Andreas Efstathiou·Suzy Jones·Peter Eisenhardt·Carrie Bridge·Jinwen Wu·Colin J. Lonsdale·Kristen Jones·Tom Jarrett·Robyn Smith
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Abstract

We present ALMA 870 micron (345 GHz) data for 49 high redshift (0.47<z<2.85), luminous (11.7 < log L(bol) (Lsun) < 14.2) radio-powerful AGN, obtained to constrain cool dust emission from starbursts concurrent with highly obscured radiative-mode black hole (BH) accretion in massive galaxies which possess a small radio jet. The sample was selected from WISE with extremely steep (red) mid-infrared (MIR) colors and with compact radio emission from NVSS/FIRST. Twenty-six sources are detected at 870 microns, and we find that the sample has large mid- to far-infrared luminosity ratios consistent with a dominant and highly obscured quasar. The rest-frame 3 GHz radio powers are 24.7 < log P3.0 GHz (W/Hz) < 27.3, and all sources are radio-intermediate or radio-loud. BH mass estimates are 7.7 < log M(BH) (Msun) < 10.2. The rest frame 1-5 um SEDs are very similar to the "Hot DOGs" (Hot Dust Obscured Galaxies), and steeper (redder) than almost any other known extragalactic sources. ISM masses estimated for the ALMA detected sources are 9.9 < log M(ISM) (Msun) < 11.75 assuming a dust temperature of 30K. The cool dust emission is consistent with star formation rates (SFRs) reaching several thousand Msun/yr, depending on the assumed dust temperature, however we cannot rule out the alternative that the AGN powers all the emission in some cases. Our best constrained source has radiative transfer solutions with ~ equal contributions from an obscured AGN and a young (10-15 Myr) compact starburst.

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Carol J. Lonsdale, Mark Lacy, Amy E. Kimball, Andrew Blain, Mark Whittle, Belinda Wilkes, Dan Stern, Jim Condon, Minjin Kim, Roberto J. Assef, Chao-Wei Tsai, Andreas Efstathiou, Suzy Jones, Peter Eisenhardt, Carrie Bridge, Jinwen Wu, Colin J. Lonsdale, Kristen Jones, Tom Jarrett, Robyn Smith. 2015-09-01. Radio Jet Feedback and Star Formation in Heavily Obscured Quasars at Redshifts ~0.3-3, I: ALMA Observations. https://doi.org/10.1088/0004-637x/813/1/45

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