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Context. The Large Magellanic Cloud (LMC) is rich in supernova remnants (SNRs), which can be investigated in detail with radio, optical, and X-ray observations. SNRJ0453-6829 is an X-ray and radio-bright remnant in the LMC, within which previous studies revealed the presence of a pulsar wind nebula (PWN), making it one of the most interesting SNRs in the Local Group of galaxies. Aims. We study the emission of SNRJ0453-6829 to improve our understanding of its morphology, spectrum, and thus the emission mechanisms in the shell and the PWN of the remnant. Methods. We obtained new radio data with the Australia Telescope Compact Array and analysed archival XMM-Newton observations of SNRJ0453-6829. We studied the morphology of SNRJ0453-6829 from radio, optical, and X-ray images and investigated the energy spectra in the different parts of the remnant. Results. Our radio results confirm that this LMC SNR hosts a typical PWN. The prominent central core of the PWN exhibits a radio spectral index αCore of -0.04 ± 0.04, while in the rest of the SNR shell the spectral slope is somewhat steeper with αShell = -0.43 ± 0.01. We detect regions with a mean polarisation of P (12 ± 4)% at 6 cm and (9 ± 2)% at 3 cm. The full remnant is of roughly circular shape with dimensions of (31±1) pc × (29±1) pc. The spectral analysis of the XMM-Newton EPIC and RGS spectra allowed us to derive physical parameters for the SNR. Somewhat depending on the spectral model, we obtain for the remnant a shock temperature of around 0.2 keV and estimate the dynamical age to 12 000-15 000 years. Using a Sedov model we further derive an electron density in the X-ray emitting material of 1.56 cm-3, typical for LMC remnants, a large swept-up mass of 830 M☉, and an explosion energy of 7.6 × 1050 erg. These parameters indicate a well evolved SNR with an X-ray spectrum dominated by emission from the swept-up material. [ABSTRACT FROM AUTHOR]

ABSTRACT We report the Australia Telescope Compact Array (ATCA) and ROSAT detection of supernova remnant (SNR) J0529−6653 in the Large Magellanic Cloud (LMC) which is positioned in the projected vicinity of the known radio pulsar PSR B0529−66. In the radio continuum frequencies, this LMC object follows a typical SNR structure of a shell morphology with brightened regions in the south-west. It exhibits an almost circular shape of D= 33 × 31 pc (1-pc uncertainty in each direction) and radio spectral index of α=−0.68 ± 0.03 - typical for mid-age SNRs. We also report detection of polarized regions with a peak value of ∼17 ± 7 per cent at 6 cm. An investigation of ROSAT images produced from merged Position Sensitive Proportional Counter (PSPC) data reveals the presence of extended X-ray emission coincident with the radio emission of the SNR. In X-rays, the brightest part is in the north-east. We discuss various scenarios with regard to the SNR-pulsar association with emphasis on the large age difference, lack of a pulsar trail and no prominent point-like radio or X-ray source. [ABSTRACT FROM AUTHOR]