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arXiv · 1304.0495

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

L. M. Bozzetto·M. D. Filipović·E. J. Crawford·M. Sasaki·P. Maggi·F. Haberl·D. Urošević·J. L. Payne·A. Y. De Horta·M. Stupar·R. Gruendl·J. Dickel
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Abstract

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 x 28 pc (1-pc uncertainty in each direction). It exhibits a radio spectrum with the intrinsic synchrotron spectral index of alpha= -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^-2. 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.

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L. M. Bozzetto, M. D. Filipović, E. J. Crawford, M. Sasaki, P. Maggi, F. Haberl, D. Urošević, J. L. Payne, A. Y. De Horta, M. Stupar, R. Gruendl, J. Dickel. 2013-04-01. Multifrequency study of SNR J0533-7202, a new supernova remnant in the LMC. https://doi.org/10.1093/mnras%2Fstt568

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