GBT20B-328

HI gas properties of post-merger remnant galaxies

Abstract

We propose to characterize the HI gas properties of post-merger galaxies, a well-defined, significant phase in merging galaxies. These galaxies probe the "coalesced" late stage of major mergers, lying between ultra luminous infrared galaxies (ULIRGs) and quenched elliptical galaxies and hence sample a key time step in major mergers. The morphologies of these systems are characterized by shells and strong tidal distortions while their colors span the blue sequence to red cloud. This is the phase in which galaxies are expected to be undergoing quenching, either by strong starburst/supernova driven winds or a central AGN. We propose to obtain HI single dish observations of a sub-sample of 112 post-merger galaxies, with 0.02<z<0.06 and 9.0< Log M <12, with and without low luminosity AGN. Together with 153 galaxies with archival HI data from the ALFALFA survey, we will investigate the role of AGN feedback on quenching. Specifically, we will characterize the fractional HI mass excess/deficit in these merger remnants as a function of stellar mass, star formation rate, AGN luminosity, and merger stage as defined by the surface brightness of the tidal tails.

Investigators

Name	Institution
Karen Masters	Haverford College
GBT Operator	Green Bank Observatory
Preethi Nair *	Alabama at Tuscaloosa, University of
David Stark	Space Telescope Science Institute; Haverford College
Jimmy Irwin	Alabama at Tuscaloosa, University of
Wenhao Li	Alabama at Tuscaloosa, University of
Jeremy Bailin	Alabama at Tuscaloosa, University of

* indicates the PI