University of Maryland
4:30 PM Monday, April 24, 2023
Talk Recording

Emil Polisensky
Naval Research Laboratory

The VLITE View of the Dynamic Radio Sky

For more than eight years, the U.S. Naval Research Laboratory and National Radio Astronomy Observatory have been running a novel experiment on the Karl G. Jansky Very Large Array (VLA). The VLA Low- band Ionosphere and Transient Experiment (VLITE) is a commensal observing mode that leverages the infrastructure of the VLA to expand its capabilities with a separate scientific data stream. VLITE records data at a central frequency of 340 MHz from the prime focus receivers in parallel with all VLA observations utilizing the 1-50 GHz Cassegrain focus receivers. This tapping of the independent optical path of the prime focus receivers allows an additional 6000 hours per year of data acquisition. Additionally, a special mode was developed to enable VLITE observations during the on-the-fly observing mode of the 3 GHz VLA Sky Survey (VLASS). This data is independently processed to generate a parallel VLITE Commensal Sky Survey (VCSS).

VLITE’s growing data archive already includes over 50,000 hours of data and 500,000 images with millions of radio emitters. This is a rich resource capable of probing variable and transient phenomena on minute to decade timescales over 80% of the sky. However, the VLA’s cycling array configuration and optical path that enable VLITE's commensal observing also present unique obstacles for realizing the potential of this database for science. I will present an overview of the VLITE system, the data analysis challenges we faced, as well as highlights of its scientific achievements and avenues for future research.