English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We present the results of a 21-cm HI survey of 27 local massive gas-richlate-stage mergers and merger remnants with the Robert C. Byrd Green BankTelescope (GBT). These remnants were selected from the Quasar/ULIRG EvolutionStudy (QUEST) sample of ultraluminous infrared galaxies (ULIRGs; L$_{8-1000 \mum} > 10^{12}$ L$_\odot$) and quasars; our targets are all bolometricallydominated by active galactic nuclei (AGN) and sample the later phases of theproposed ULIRG-to-quasar evolutionary sequence. We find the prevalence of HIabsorption (emission) to be 100% (29%) in ULIRGs with HI detections, 100% (88%)in FIR-strong quasars, and 63% (100%) in FIR-weak quasars. The absorptionfeatures are associated with powerful neutral outflows that change from beingmainly driven by star formation in ULIRGs to being driven by the AGN in thequasars. These outflows have velocities that exceed 1500 km s$^{-1}$ in somecases. Unexpectedly, we find polarization-dependent HI absorption in 57% of ourspectra (88% and 63% of the FIR-strong and FIR-weak quasars, respectively). Weattribute this result to absorption of polarized continuum emission from thesesources by foreground HI clouds. About 60% of the quasars displaying polarizedspectra are radio-loud, far higher than the $\sim$10% observed in the generalAGN population. This discrepancy suggests that radio jets play an importantrole in shaping the environments in these galaxies. These systems may representa transition phase in the evolution of gas-rich mergers into "mature" radiogalaxies.

GBT Detection of Polarization-dependent HI Absorption and HI Outflows in Local ULIRGs and Quasars