Very Long Baseline Interferometry Imaging of the Very Large Array Sky Survey Detections

We report the results of four 6-hr Very Large Baseline Array (VLBA) pilot observations at 5 GHz, exploring the possibility of using Very Large Array Sky Survey (VLASS) detected radio sources above1 mJy as an input catalog for VLBA science. The astronomical results and array engineering data from the four pilot epochs were used to characterize the observing effciency and scientific performance of the VLBA using these inputs. In a follow-up observation, we achieved significant improvements to the observing efficiency in survey mode. Initial data calibration and imaging was carried out in AIPS, and we are building a Common Astronomy Software Application (CASA) pipeline for future epochs. The initial results obtained from these pilot runs suggest that an all-sky VLBA survey down to a detection limit of 3-5 mJy is feasible with current VLA/VLBA technical capabilities within the next few years.