Evaluating Imaging Quality on LWA-SV’s E-field Parallel Imaging Correlator (EPIC) using WSClean

The E-Field Parallel Imaging Correlator (EPIC, Thyagarajan et al. 2017) architecture has been shown to be an effective method for high-cadence direct radio imaging and has been demonstrated on the Long Wavelength Array Sevilleta (LWA-SV) station (Kent et al. 2019a,b; Krishnan et al. 2023). Improvements to the efficiency and hardware of the LWA implementation of EPIC have allowed access to imaging at up to quadruple the image size (256x256 pixels) and double the bandwidth (6.6 MHz) of previous studies. However, EPIC’s imager has yet to be cross-examined with off the shelf imaging software used by other radio interferometers such as the LWA, Low Frequency Array (LOFAR, van Haarlem et al. 2013), or the Murchison Widefield Array (MWA, Tingay et al. 2013) Here, we present validation work to aid in the commissioning of the LWA-EPIC system by comparing results of images processed onboard, with those correlated offline and imaged using WSClean (Offringa et al. 2014). Comparing these results provides essential insight on the fidelity EPIC’s implementation on the LWA, and its broader applications to other comparable low-frequency radio telescopes.