Multifrequency study of SNR J0533–7202, a new supernova remnant in the LMC

We present a detailed study of Australia Telescope Compact Array (ATCA) observations of a newly discovered Large Magellanic Cloud (LMC) supernova remnant (SNR), SNR J0533–7202. This object follows a horseshoe morphology, with a size 37 pc × 28 pc (1-pc uncertainty in each direction). It exhibits a radio spectrum with the intrinsic synchrotron spectral index of α=–0.47±0.06 between 73 and 6 cm. We report detections of regions showing moderately high fractional polarisation at 6 cm, with a peak value of 36±6% and a mean fractional polarisation of 12±7%. We also estimate an average rotation measure across the remnant of –591 rad m. The current lack of deep X-ray observation precludes any conclusion about high-energy emission from the remnant. The association with an old stellar population favours a thermonuclear supernova origin of the remnant.