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GBT Detection of Polarization-Dependent HI Absorption and HI Outflows in Local ULIRGs and QuasarsWe present the results of a 21-cm HI survey of 27 local massive gas-rich late-stage mergers and merger remnants with the Green Bank Telescope (GBT). These remnants were selected from the Quasar/ULIRG Evolution Study (QUEST) sample of ultraluminous infrared galaxies (ULIRGs; L(sub 8 - 1000 micron) > 10(exp 12) solar L) and quasars; our targets are all bolometrically dominated by active galactic nuclei (AGN) and sample the later phases of the proposed ULIRG-to-quasar evolutionary sequence. We find the prevalence of HI absorption (emission) to be 100% (29%) in ULIRGs with HI detections, 100% (88%) in FIR-strong quasars, and 63% (100%) in FIR-weak quasars. The absorption features are associated with powerful neutral outflows that change from being mainly driven by star formation in ULIRGs to being driven by the AGN in the quasars. These outflows have velocities that exceed 1500 km/s in some cases. Unexpectedly, we find polarization-dependent HI absorption in 57% of our spectra (88% and 63% of the FIR-strong and FIR-weak quasars, respectively). We attribute this result to absorption of polarized continuum emission from these sources by foreground HI clouds. About 60% of the quasars displaying polarized spectra are radio-loud, far higher than the approx 10% observed in the general AGN population. This discrepancy suggests that radio jets play an important role in shaping the environments in these galaxies. These systems may represent a transition phase in the evolution of gas-rich mergers into "mature" radio galaxies.
Document ID
20130012554
Acquisition Source
Goddard Space Flight Center
Document Type
Preprint (Draft being sent to journal)
Authors
Teng, Stacy H.
(Oak Ridge Associated Universities Greenbelt, MD, United States)
Veilleux, Sylvain
(Maryland Univ. College Park, MD, United States)
Baker, Andrew J.
(Rutgers - The State Univ. Piscataway, NJ, United States)
Date Acquired
August 27, 2013
Publication Date
January 1, 2013
Subject Category
Astronomy
Report/Patent Number
GSFC-E-DAA-TN7694
Funding Number(s)
CONTRACT_GRANT: NNH06CC03B
Distribution Limits
Public
Copyright
Public Use Permitted.
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