Multi-frequency study of DEM L299 in the Large Magellanic Cloud

Abstract

Aims. We have studied the H ii region DEM L299 in the Large Magellanic Cloud (LMC) to understand its physical characteristics and morphology in different wavelengths. Methods. We performed a spectral analysis of archived XMM-Newton EPIC data and studied the morphology of DEM L299 in X-ray, optical, and radio wavelengths. We used Hα, [S ii], and [O iii] data from the Magellanic Cloud Emission Line Survey (MCELS) and radio 21 cm line data from the Australia Telescope Compact Array (ATCA) and the Parkes Telescope as well as radio continuum data (3 cm, 6 cm, 20 cm, 36 cm) from ATCA and from the Molonglo Synthesis Telescope (MOST). Results. Our morphological studies imply that, in addition to the supernova remnant SNR B0543-68.9 reported in previous studies, a superbubble also overlaps the SNR in projection. The position of the SNR is clearly defined through the [S ii]/Hα flux ratio image.Moreover, the optical images show a shell-like structure that is located farther to the north and is filled with diffuse X-ray emission, which again indicates the superbubble. Radio 21 cm line data show a shell around both objects. Radio continuum data show diffuse emission at the position of DEM L299, which appears clearly distinguished from the H ii region LHA 120-N 164 that lies south-west of it. We determined the spectral index of SNR B0543-68.9 to be α = −0.34, which indicates the dominance of thermal emission and therefore a rather mature remnant. We determined the basic properties of the diffuse X-ray emission for the SNR, the superbubble, and a possible blowout region of the bubble, as suggested by the optical and X-ray data. We obtained an age of (8.9 +9.2 −5.4 ) kyr for the SNR and a temperature of (0.64 +0.73 −0.20 ) keV for the hot gas inside the SNR, as well as a thermal energy content and temperature of the hot gas inside the superbubble of (4.3 +8.1 −2.6 ) × 10 50 φ 0.5 erg and (0.74 +0.36 −0.30 ) keV, with φ being the gas-filling factor. Conclusions. We conclude that DEM L299 consists of a superposition of SNR B0543-68.9 and a superbubble, which we identified based on optical data.

26Al kinematics: superbubbles following the spiral arms?

“…Here, k is Boltzmann's constant, m p the proton mass, T (T 0.5 ) the temperature (in units of 0.5 keV), and the numerical factor is calculated for a fully ionised plasma of 90 per cent hydrogen and 10 per cent helium by volume. Measurements of superbubble temperatures range from 0.1 keV to about 1 keV (e.g., Dunne et al 2001;Jaskot et al 2011;Sasaki et al 2011;Kavanagh et al 2012;Warth et al 2014), in good agreement with expectations, if instabilities and mixing are taken into account .…”

Statistical Analysis of Supernova Remnants in the Large Magellanic Cloud

“…Some recent studies include: Bojičić et al (2007), Cajko et al (2009), Crawford et al (2008Crawford et al ( , 2010Crawford et al ( , 2014, Bozzetto et al (2010), Grondin et al (2012), Bozzetto et al (2012d,b,a,c), de Horta et al (2012);De Horta et al (2014), Kavanagh et al (2013), Bozzetto et al (2013), Brantseg et al (2014), Bozzetto et al (2014b,a); Bozzetto & Filipović (2014), Warth et al (2014), Maggi et al (2014), Reid et al (2015), Kavanagh et al (2015a,b,c), Bozzetto et al (2015) and Kavanagh et al (2016).…”

X-Ray Luminosity and Size Relationship of Supernova Remnants in the LMC

“…We include all the diffuse X-ray emission region and [S II] enhanced filaments, and measure a size of 100×50 pc. A smaller SNR size, ∼55 pc, has been reported by Warth et al (2014) and Maggi et al (2016) based on the diffuse X-ray emission and a surrounding [S II]-enhanced filament. The large discrepancy between these two size measurements illustrate the difficulty in determining SNR sizes in a complex environment confused by other energetic feedback processes from massive stars.…”