The Role of Radio Observations in Studies of Infrared-Bright Galaxies: Prospects for a next-generation Very Large Array

TL;DR

This paper discusses how the next-generation Very Large Array will revolutionize our understanding of galaxy formation by enabling detailed, dust-unbiased studies of molecular gas and star formation in early universe galaxies.

Contribution

It highlights the potential of the next-generation VLA to study cold molecular gas and star formation in high-redshift galaxies with unprecedented resolution and sensitivity.

Findings

Next-generation VLA will enable sub-kpc scale observations of molecular gas.

It will allow unbiased studies of star formation in dusty, infrared-bright galaxies.

The technology will improve understanding of galaxy evolution during peak star formation epochs.

Abstract

The bulk of the present-day stellar mass was formed in galaxies when the universe was less than half its current age (i.e., $1 \lesssim z \lesssim 3$). While this likely marks one of the most critical time periods for galaxy evolution, we currently do not have a clear picture on the radial extent and distribution of cold molecular gas and associated star formation within the disks of galaxies during this epoch. Such observations are essential to properly estimate the efficiency at which such galaxies convert their gas into stars, as well as to account for the various energetic processes that govern this efficiency. Long-wavelength (i.e., far-infrared--to--radio) observations are critical to penetrate the high-levels of extinction associated with dusty, infrared-bright galaxies that are driving the stellar mass assembly at such epochs. In this article we discuss how the next-generation Very Large Array will take a transformative step in our understanding of galaxy formation and evolution by delivering the ability to simultaneously study the relative distributions molecular gas and star formation on sub-kpc scales unbiased by dust for large populations of typical galaxies in the early universe detected by future far-infrared space missions.