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The Large Magellanic Cloud (LMC) hosts a rich population of supernova remnants (SNRs), our knowledge of which is the most complete of any galaxy. However, there remain many candidate SNRs, identified through optical and radio observations where additional X-ray data can confirm their SNR nature and provide details on their physical properties. In this paper, we present XMM–Newton observations that provide the first deep X-ray coverage of ten objects, comprising eight candidates and two previously confirmed SNRs. We perform multifrequency studies using additional data from the Magellanic Cloud Emission Line Survey (MCELS) to investigate their broad-band emission and used Spitzer data to understand the environment in which the objects are evolving. We confirm seven of the eight candidates as bona-fide SNRs. We used a multifrequency morphological study to determine the position and size of the remnants. We identify two new members of the class of evolved Fe-rich remnants in the Magellanic Clouds (MCs), several SNRs well into their Sedov-phase, one SNR likely projected towards a H  ii region, and a faint, evolved SNR with a hard X-ray core which could indicate a pulsar wind nebula. Overall, the seven newly confirmed SNRs represent a ∼10-per cent increase in the number of LMC remnants, bringing the total number to 71, and provide further insight into the fainter population of X-ray SNRs. [ABSTRACT FROM AUTHOR]

Aims.We present a multi-wavelength analysis of the evolved supernova remnants MCSNR J05067025 and MCSNR J0527-7104 in the Large Magellanic Cloud. Methods. We used observational data from XMM-Newton, the Australian Telescope Compact Array, and the Magellanic Cloud Emission Line Survey to study their broad-band emission and used Spitzer and Hi data to gain a picture of the environment into which the remnants are expanding. We performed a multi-wavelength morphological study and detailed radio and X-ray spectral analyses to determine their physical characteristics. Results. Both remnants were found to have bright X-ray cores, dominated by Fe L-shell emission, which is consistent with reverse shock-heated ejecta with determined Fe masses in agreement with Type Ia explosion yields. A soft X-ray shell, which is consistent with swept-up interstellar medium, was observed in MCSNR J0506-7025, suggestive of a remnant in the Sedov phase. Using the spectral fit results and the Sedov self-similar solution, we estimated the age of MCSNR J0506-7025 to be ~16-28 kyr, with an initial explosion energy of (0.07-0.84) × 1051 erg. A soft shell was absent in MCSNR J0527-7104, with only ejecta emission visible in an extremely elongated morphology that extends beyond the optical shell. We suggest that the blast wave has broken out into a low density cavity, allowing the shock heated ejecta to escape. We find that the radio spectral index of MCSNR J0506-7025 is consistent with the standard -0:5 for supernova remnants. Radio polarisation at 6 cm indicates a higher degree of polarisation along the western front and at the eastern knot with a mean fractional polarisation across the remnant of P ≅ (20 ± 6)%. Conclusions. The detection of Fe-rich ejecta in the remnants suggests that both resulted from Type Ia explosions. The newly identified Fe-rich cores in MCSNR J0506-7025 and MCSNR J0527-7104 make them members of the expanding class of evolved Fe-rich remnants in the Magellanic Clouds. [ABSTRACT FROM AUTHOR]

Aims. We present an X-ray study of the supernova remnant SNR J0533-7202 in the Large Magellanic Cloud (LMC) and determine its physical characteristics based on its X-ray emission. Methods. We observed SNR J0533-7202 with XMM-Newton (background flare-filtered exposure times of 18 ks EPIC-pn and 31 ks EPIC-MOS1, EPIC-MOS2). We produced X-ray images of the supernova remnant, performed an X-ray spectral analysis, and compared the results to multi-wavelength studies. Results. The distribution of X-ray emission is highly non-uniform, with the south-west region much brighter than the north-east. The detected X-ray emission is correlated with the radio emission from the remnant.We determine that this morphology is most likely due to the supernova remnant expanding into a non-uniform ambient medium and not an absorption e ect. We estimate the remnant size to be 53:9 (±3:4) × 43:6 (±3:4) pc, with the major axis rotated ∼64° east of north. We find no spectral signatures of ejecta emission and infer that the X-ray plasma is dominated by swept up interstellar medium. Using the spectral fit results and the Sedov self-similar solution, we estimate the age of SNR J0533-7202 to be ∼17-27 kyr, with an initial explosion energy of (0:09-0:83) × 1051 erg. We detected an X-ray source located near the centre of the remnant, namely XMMU J053348.2-720233. The source type could not be conclusively determined due to the lack of a multi-wavelength counterpart and low X-ray counts. We found that it is likely either a background active galactic nucleus or a low-mass X-ray binary in the LMC. Conclusions. We detected bright thermal X-ray emission from SNR J0533-7202 and determined that the remnant is in the Sedov phase of its evolution. The lack of ejecta emission prohibits us from typing the remnant with the X-ray data. Therefore, the likely Type Ia classification based on the local stellar population and star formation history reported in the literature cannot be improved upon. [ABSTRACT FROM AUTHOR]

Context. The high sensitivity of the XMM-Newton instrumentation offers the opportunity to study faint and extended sources in the Milky Way and nearby galaxies such as the Large Magellanic Cloud (LMC) in detail. The ROSAT PSPC survey of the LMC has revealed more than 700 X-ray sources, among which there are 46 supernova remnants (SNRs) and candidates. Aims. We have observed the field around one of the most promising SNR candidates in the ROSAT PSPC catalogue, labelled [HP99] 456 with XMM-Newton, to determine its nature. Methods. We investigated the XMM-Newton data along with new radio-continuum, near infrared and optical data. In particular, spectral and morphological studies of the X-ray and radio data were performed. Results. The X-ray images obtained in different energy bands reveal two different structures. Below 1.0 keV the X-ray emission shows the shell-like morphology of an SNR with a diameter of ~73 pc, one of the largest known in the LMC. For its thermal spectrum we estimate an electron temperature of (0.49 ± 0.12) keV assuming non-equilibrium ionisation. The X-ray images above 1.0 keV reveal a less extended source within the SNR emission, located 1' west of the centre of the SNR and coincident with bright point sources detected in radio-continuum. This hard component has an extent of 0.9' (i.e. ~13 pc at a distance of ~50 kpc) and a non-thermal spectrum. The hard source coincides in position with the ROSAT source [HP99] 456 and shows an indication for substructure. Conclusions. We firmly identify a new SNR in the LMC with a shell-like morphology and a thermal spectrum. Assuming the SNR to be in the Sedov phase yields an age of ~23 kyr. We explore possible associations of the hard non-thermal emitting component with a pulsar wind nebula (PWN) or background active galactic nucleus (AGN). [ABSTRACT FROM AUTHOR]

We report the discovery of a new high-mass X-ray binary pulsar, XMMU J050722.1−684758, possibly associated with the supernova remnant (SNR) MCSNR J0507−6847 in the Large Magellanic Cloud, using XMM–Newton X-ray observations. Pulsations with a periodicity of 570 s are discovered from the Be X-ray binary XMMU J050722.1−684758 confirming its nature as a HMXB pulsar. The HMXB is located near the geometric centre of the SNR MCSNR J0507−6847(0.9 arcmin from the centre) which supports the XRB-SNR association. The estimated age of the SNR is 43–63 kyr years which points to a middle aged to old SNR. The large diameter of the SNR combined with the lack of distinctive shell counterparts in optical and radio indicates that the SNR is expanding into the tenuous environment of the superbubble N103. The estimated magnetic field strength of the neutron star is B ≳ 1014 G assuming a spin equilibrium condition which is expected from the estimated age of the parent remnant and assuming that the measured mass-accretion rate remained constant throughout. [ABSTRACT FROM AUTHOR]

We report the discovery of a very young high-mass X-ray binary (HMXB) system associated with the supernova remnant (SNR) MCSNR J0513-6724 in the Large Magellanic Cloud (LMC), using XMM–Newton X-ray observations. The HMXB is located at the geometrical centre of extended soft X-ray emission, which we confirm as an SNR. The HMXB spectrum is consistent with an absorbed power law with spectral index ∼1.6 and a luminosity of 7 × 1033 erg s−1 (0.2–12 keV). Tentative X-ray pulsations are observed with a periodicity of 4.4 s and the OGLE I -band light curve of the optical counterpart from more than 17.5 yr reveals a period of 2.2324 ± 0.0003 d, which we interpret as the orbital period of the binary system. The X-ray spectrum of the SNR is consistent with non-equilibrium shock models as expected for young/less evolved SNRs. From the derived ionization time-scale we estimate the age of the SNR to be <6 kyr. The association of the HMXB with the SNR makes it the youngest HMXB, in the earliest evolutionary stage known to date. An HMXB as young as this can switch on as an accreting pulsar only when the spin period has reached a critical value. Under this assumption, we obtain an upper limit to the magnetic field of <5 × 1011 G. This implies several interesting possibilities including magnetic field burial, possibly by an episode of post-supernova hyper-critical accretion. Since these fields are expected to diffuse out on a time-scale of 103–104 yr, the discovery of a very young HMXB can provide us the unique opportunity to observe the evolution of the observable magnetic field for the first time in X-ray binaries. [ABSTRACT FROM AUTHOR]