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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]

Aims. We present a detailed study of the superbubble 30 Dor C and the newly identified supernova remnant MCSNR J0536-6913 in the Large Magellanic Cloud. Methods. All available XMM-Newton data (flare-filtered exposure times of 420 ks EPIC-pn, 556 ks EPIC-MOS1, 614 ks EPICMOS2) were used to characterise the thermal X-ray emission in the region. An analysis of the non-thermal X-ray emission is also presented and discussed in the context of emission mechanisms previously suggested in the literature. These data are supplemented by X-ray data from Chandra, optical data from the Magellanic Cloud Emission Line Survey, and radio data from the Australia Telescope Compact Array and the Molonglo Observatory Synthesis Telescope. Results. The brightest thermal emission towards 30 Dor C was found to be associated with a new supernova remnant, MCSNR J0536-6913. X-ray spectral analysis of MCSNR J0536-6913 suggested an ejecta-dominated remnant with lines of O, Ne, Mg, and Si, and a total 0:3-10 keV X-ray luminosity of ~8*1034 erg s-1. Based on derived ejecta abundance ratios, we determined the mass of the stellar progenitor to be either ~18 M or as high as>40 M_sun, though the spectral fits were subject to assumptions (e.g., uniform temperature and well-mixed ejecta). The thermal emission from the SB exhibited enrichment by alpha-process elements, evidence for a recent core-collapse SNR interaction with the SB shell. We detected non-thermal X-ray emission throughout 30 Dor C, with the brightest regions being highly correlated with the H-alpha and radio shells. We created a non-thermal spectral energy distribution for the north-eastern shell of 30 Dor C which was best-fit with an exponentially cut-off synchrotron model. Conclusions. Thermal X-ray emission from 30 Dor C is very complex, consisting of a large scale superbubble emission at the eastern shell wall with the brightest emission due to MCSNR J0536??6913. The fact that the non-thermal spectral energy distribution of the superbubble shell was observed to roll-off is further evidence that the non-thermal X-ray emission from 30 Dor C is synchrotron in origin. [ABSTRACT FROM AUTHOR]

Context. The Large Magellanic Cloud (LMC) hosts a rich and varied population of supernova remnants (SNRs). Optical, X-ray, and radio observations are required to identify these SNRs, as well as to ascertain the various processes responsible for the large array of physical characteristics observed. Aims. In this paper we attempted to confirm the candidate SNR [HP99] 1234, identified in X-rays with ROSAT, as a true SNR by supplementing these X-ray data with optical and radio observations. Methods. Optical data from the Magellanic Cloud Emission Line Survey (MCELS) and new radio data from the Molonglo Observatory Synthesis Telescope (MOST), in addition to the ROSAT X-ray data, were used to perform a multiwavelength morphological analysis of this candidate SNR. Results. An approximately ellipsoidal shell of enhanced [S ii] emission, typical of an SNR ([S ii]/Hα > 0.4), was detected in the optical. This enhancement is positionally coincident with faint radio emission at λ = 36 cm. Using the available data we estimated the size of the remnant to be ∼5.1′ x 4.0′ (∼75 pc x 59 pc). However, the measurement along the major-axis was somewhat uncertain due to a lack of optical and radio emission at its extremities and the poor resolution of the X-ray data. Assuming this SNR is in the Sedov phase and adopting the ambient mass density of 1.2 × 10-25 g cm-3 measured in a nearby Hii region, an age estimate of ∼25 kyr was calculated for a canonical initial explosion energy of 1051 erg. However, this age estimate should be treated cautiously due to uncertainties on the adopted parameters. Analysis of the local stellar population suggested a type Ia event as a precursor to this SNR, however, a core-collapse mechanism could not be ruled out due to the possibility of the progenitor being a runaway massive star. Conclusions. With the detection of X-ray, radio and significant optical line emission with enhanced [S ii], this object was confirmed as an SNR to which we assign the identifier MCSNR J0527-7104. [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]

Aims. We present a detailed multi-wavelength study of four new supernova remnants (SNRs) in the Large Magellanic Cloud (LMC). The objects were identified as SNR candidates in X-ray observations performed during the survey of the LMC with XMM-Newton. Methods. Data obained with XMM-Newton are used to investigate the morphological and spectral features of the remnants in X-rays. We measure the plasma conditions, look for supernova (SN) ejecta emission, and constrain some of the SNR properties (e.g. age and ambient density). We supplement the X-ray data with optical, infrared, and radio-continuum archival observations, which allow us to understand the conditions resulting in the current appearance of the remnants. Based on the spatially-resolved star formation history (SFH) of the LMC together with the X-ray spectra, we attempt to type the supernovae that created the remnants. Results. We confirm all four objects as SNRs, to which we assign the names MCSNR J0508-6830, MCSNR J0511-6759, MCSNR J0514-6840, and MCSNR J0517-6759. In the first two remnants, an X-ray bright plasma is surrounded by very faint [S ii] emission. The emission from the central plasma is dominated by Fe L-shell lines, and the derived iron abundance is greatly in excess of solar. This establishes their type Ia (i.e. thermonuclear) SN origin. They appear to be more evolved versions of other Magellanic Cloud iron-rich SNRs which are centrally-peaked in X-rays. From the two other remnants (MCSNR J0514-6840 and MCSNR J0517-6759), we do not see ejecta emission. At all wavelengths at which they are detected, the local environment plays a key role in their observational appearance. We present evidence that MCSNR J0517-6759 is close to and interacting with a molecular cloud, suggesting a massive progenitor. [ABSTRACT FROM AUTHOR]

Context. The Large Magellanic Cloud (LMC) is an ideal target for the study of an unbiased and complete sample of supernova remnants (SNRs). We started an X-ray survey of the LMC with XMM-Newton, which, in combination with observations at other wavelengths, will allow us to discover and study remnants that are either even fainter or more evolved (or both) than previously known. Aims. We present new X-ray and radio data of the LMC SNR candidate DEM L205, obtained by XMM-Newton and ATCA, along with archival optical and infrared observations. Methods. We use data at various wavelengths to study this object and its complex neighbourhood, in particular in the context of the star formation activity, past and present, around the source. We analyse the X-ray spectrum to derive some remnant's properties, such as age and explosion energy. Results. Supernova remnant features are detected at all observed wavelengths : soft and extended X-ray emission is observed, arising from a thermal plasma with a temperature kT between 0.2 keV and 0.3 keV. Optical line emission is characterised by an enhanced [S ii]-to-Hα ratio and a shell-like morphology, correlating with the X-ray emission. The source is not or only tentatively detected at near-infrared wavelengths (shorter than 10 μm), but there is a detection of arc-like emission at mid and far-infrared wavelengths (24 and 70 μm) that can be unambiguously associated with the remnant. We suggest that thermal emission from dust heated by stellar radiation and shock waves is the main contributor to the infrared emission. Finally, an extended and faint non-thermal radio emission correlates with the remnant at other wavelengths and we find a radio spectral index between -0.7 and -0.9, within the range for SNRs. The size of the remnant is ∼79 X64 pc and we estimate a dynamical age of about 35 000 years. Conclusions. We definitely confirm DEM L205 as a new SNR. This object ranks amongst the largest remnants known in the LMC. The numerous massive stars and the recent outburst in star formation around the source strongly suggest that a core-collapse supernova is the progenitor of this remnant. [ABSTRACT FROM AUTHOR]

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. SNR-J0453-6829 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 SNR-J0453-6829 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 SNR-J0453-6829. We studied the morphology of SNR-J0453-6829 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]

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]