GBT22B-248

Mapping HCN and HCO+ in Local Luminous Infrared Mergers

Abstract

Luminous infrared galaxies (LIRGs) are the most extreme star-forming galaxies in the local Universe and are primarily interacting gas-rich spirals at z~0. They provide the ideal laboratories to conduct in-depth studies of intense star-forming environments that are more common at high-z. Global measurements argue that the prodigious star formation in LIRGs are simply driven by their abundance of dense gas that emits HCN and HCO+ relative to bulk molecular gas traced by CO, and dense gas form stars at constant efficiency. However, recent spatially-resolved studies of nearby disc galaxies instead have shown strong environmental dependence of dense gas distribution and its relation to star formation. To better understand what drives the intense star formation in LIRGs and likely at high-z, we propose a pilot study using GBT/Argus to map spatially-resolved kpc scale J=1-0 HCN and HCO+ emission in four local starburst-dominated LIRGs at different merger stages. Combined with rich multi-wavelength datasets that trace star formation rate, stellar mass and the bulk molecular gas content at matched resolution, the proposed observations will allow us to investigate whether, where and how dense gas regulates star formation in the extreme merging environments of local LIRGs on sub-galactic scales.

Investigators

Name	Institution
Yiqing Song *	Virginia, University of; European Southern Observatory
Amanda Kepley	National Radio Astronomy Observatory
Aaron Evans	National Radio Astronomy Observatory; Virginia, University of
Dave Frayer	Green Bank Observatory
Kimberly Emig	National Radio Astronomy Observatory
Sean Linden	Arizona, University of
Ilsang Yoon	National Radio Astronomy Observatory
Devaky Kunneriath	National Radio Astronomy Observatory; Akademie ved Ceske republiky
Alejandro Saravia	Virginia, University of
Erik Rosolowsky	British Columbia at Okanagan, University of ; Alberta, University of
Loreto Barcos	National Radio Astronomy Observatory; Virginia, University of; Joint ALMA Observatory
George Privon	National Radio Astronomy Observatory; Florida, University of

* indicates the PI