Knox

We have carried out new 6 and 20 cm observations of M33 with the Jansky Very Large Array, primarily to study the properties of supernova remnants in the galaxy. Our scaled array observations have a limiting sensitivity of about 25 $mu$Jy (5 $sigma$) and a resolution of 5” (FWHM), corresponding to a spatial resolution of 20 pc at the distance of M33. We detect about 85 of the SNRs contained in the list of 137 optically identified SNRs described by Long et al. (2010), and a few additional objects from the survey of Lee & Lee (2014). A substantial fraction of the optical SNRs not detected are in regions where emission from H II recombination makes identification of non-thermal emission from the SNR difficult. We also discuss a blind search for SNRs based on the radio emission alone. Of the SNRs we detect in this search at radio wavelengths, 53 have also been detected at X-ray wavelengths. Thus we are able make a direct comparison of the X-ray, optical, and radio properties of the SNRs in M33, the first time that has been possible to a significant extent in an external spiral galaxy.