Presentation #316.01 in the session “Radio and mm Instrumentation and Surveys”.
Deep radio continuum surveys are essential for studying the complex interplay between supermassive black hole (SMBH) growth and stellar assembly over cosmic time. Observations at low radio frequencies (< 1 GHz) have the advantage of sensitivity to the older populations of cosmic ray electrons commonly associated with high-redshift radio active galactic nuclei (AGN) characterized by steep radio spectral indices, and in combination with higher-frequency data place strong constraints on the underlying emission mechanism and evolutionary stage of faint radio source populations. A novel approach to deep multi-band radio surveys is the use of commensal systems that leverage infrastructure of other radio interferometers operating at higher frequencies. An example of a pioneering instrument in this domain that is currently installed on the Karl G. Jansky Very Large Array (VLA) is the VLA Low-band Ionosphere and Transient Experiment (VLITE), which records data at 340 MHz simultaneously with regular VLA observing programs. VLITE accumulates more than 6200 hours of data per year from the VLA, making a vast - yet largely untapped - resource for enhancing the legacy value and scientific impact of VLA surveys. Here, we present our on-going deep imaging campaign of 150 hours of VLITE observations centered on the Hubble Ultra Deep Field (HUDF) and observed in the VLA A configuration. These VLITE data complement 150 hours of simultaneously observed S-band (2-4 GHz) VLA data, as well as 177 hours of prior C-band (4-8 GHz) observations. We present strategies for addressing the technical and computational challenges posed by deep, wide-field, high-angular resolution imaging in the sub-GHz regime.