Creating deep images of VLA calibrators

Among the outstanding questions in the study of extragalactic jets is that of the dominant mechanism(s) responsible for producing the X-ray emission. Of major importance for testing competing models is the availability of high-resolution radio observations at multiple frequencies, to trace the jet structure and to estimate the equipartition magnetic field. A surprising number of known kiloparsec-scale jets have no high-sensitivity, high-resolution observations with the VLA. However, many have been observed dozens to hundreds of times as calibrators for other VLA targets. These jets are thus suitable candidates for image “stacking” by combining scaled and aligned UV datasets taken over many observations.  We demonstrate a proof-of-concept by stacking 37 observations of 3C286, to produce a substantially deeper image than any individual input image. The calibration and stacking are accomplished using an automatic script that requires limited input by the user.