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arXiv · astro-ph/0305103

High resolution spectroscopy and emission line imaging of DEM L 71 with XMM-Newton

K. J. van der Heyden·J. A. M. Bleeker·J. S. Kaastra·J. Vink
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Abstract

The X-ray emission from the supernova remnant DEM L 71 is measured and analysed using the high-resolution cameras and spectrometers on board XMM-Newton. The spectrum from the outer shell is reproduced very well by two plasma components of kT = 0.3 and 0.8 keV. The abundance value from this shell is consistent with the average LMC values. More extreme temperature variations are possibly indicated by spatial variations in the O VII forbidden/resonance line ratio, which could imply that in some regions the plasma is cooling dramatically and recombining. However, an alternative and equally interesting possibility is that the variation in forbidden/resonance ratios is due to resonant scattering, which would reduce resonance line emission along lines of sight with a high O VII column density. The inner region is hotter (kT = 1.1 keV) and shows enhanced Fe and Si abundances. We estimate the Fe and Si ejecta mass to be 0.7-1.1 M_sun and 0.1--0.15 M_sun, respectively. The morphology, mass estimates and abundances strongly suggest that DEM L 71 is the result of a type Ia explosion, as indicated by previous measurements.

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K. J. van der Heyden, J. A. M. Bleeker, J. S. Kaastra, J. Vink. 2003-05-07. High resolution spectroscopy and emission line imaging of DEM L 71 with XMM-Newton. https://doi.org/10.1051/0004-6361%3A20030658

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