GBT17B-151

Extragalactic GBT+ARGUS Gas Density Survey

Abstract

Every major current theory of star formation in galaxies treats gas density as a central quantity. Differentiating between these theories requires (1) quantifying the relationship between gas density and star formation and (2) understanding what sets the gas density distribution within a galaxy. We propose the new capabilities of ARGUS to map a suite of density-sensitive mm-wave lines (HCN 1-0, HCO+ 1-0, C18O 1-0, and 13CO 1-0) across the inner 2arcmin by 2arcmin of 36 nearby galaxies. We will use these lines to measure how the gas volume density distribution changes as a function of galactic environment and, by comparing the changing density distribution to the rate of recent star formation, evaluate how density affects the ability of gas to form stars. These observations will produce a high impact, best-in-class survey of how the gas density distribution changes across galaxies, strong tests of the current leading theories of star formation in galaxies, and measurements that bridge the gap between Milky Way and extragalactic studies. This is a resubmission of a highly ranked proposal that was awarded up to 167h hours in 17A. We have incorporated the on-sky performance of ARGUS and highlighted the NSF grant support available for this program.

Investigators

Name Institution
Amanda Kepley * National Radio Astronomy Observatory
Antonio Usero Instituto Geográfico Nacional
Dave Frayer Green Bank Observatory
Molly Gallagher Ohio State University
Karin Sandstrom California at San Diego, University of; Arizona, University of; Max-Planck-Institut für Astronomie
Yiqing Song Virginia, University of; European Southern Observatory
Matteo Luisi Westminster College
Eric Koch Alberta, University of; Smithsonian Astrophysical Observatory
Jeremy Thorley
Joy Skipper Green Bank Observatory
Jennifer Donovan Meyer National Radio Astronomy Observatory
Dongwoo Chung Stanford University
Rebecca Levy Arizona, University of
Alberto Bolatto Maryland, University of
Sarah Church Stanford University
Joshua Gundersen Miami, University of
Cheoljong Lee Virginia, University of
Adam Leroy National Radio Astronomy Observatory; Ohio State University
Jialu Li Maryland, University of
Maria Jesus Jimenez Donaire Instituto Geográfico Nacional; Yebes, Centro Astronómico de
Andreas Schruba Max-Planck-Institut für extraterrestrische Physik
Eva Schinnerer National Radio Astronomy Observatory; Max-Planck-Institut für Astronomie
Andy Harris Maryland, University of
Erik Rosolowsky British Columbia at Okanagan, University of ; Alberta, University of
Frank Bigiel Bonn, Universität
Matthew Sieth Stanford University
Sarah Kessler Ohio State University
Luca Beale Virginia, University of
Kieran Cleary California Institute of Technology
Annie Hughes Max-Planck-Institut für Astronomie; Centre National de la Recherche Scientifique

* indicates the PI