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arXiv · 1004.4132

Discovery of X-Ray-Emitting O-Ne-Mg-Rich Ejecta in the Galactic Supernova Remnant Puppis A

Satoru Katsuda·Una Hwang·Robert Petre·Sangwook Park·Koji Mori·Hiroshi Tsunemi
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Abstract

We report on the discovery of X-ray--emitting O-Ne-Mg-rich ejecta in the middle-aged Galactic O-rich supernova remnant Puppis A with Chandra and XMM-Newton. We use line ratios to identify a low-ionization filament running parallel to the northeastern edge of the remnant that requires supersolar abundances, particularly for O, Ne, and Mg, which we interpret to be from O-Ne-Mg-rich ejecta. Abundance ratios of Ne/O, Mg/O, and Fe/O are measured to be ~2, ~2, and <0.3 times the solar values. Our spatially-resolved spectral analysis from the northeastern rim to the western rim otherwise reveals sub-solar abundances consistent with those in the interstellar medium. The filament is coincident with several optically emitting O-rich knots with high velocities. If these are physically related, the filament would be a peculiar fragment of ejecta. On the other hand, the morphology of the filament suggests that it may trace ejecta heated by a shock reflected strongly off the dense ambient clouds near the northeastern rim.

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Satoru Katsuda, Una Hwang, Robert Petre, Sangwook Park, Koji Mori, Hiroshi Tsunemi. 2010-04-23. Discovery of X-Ray-Emitting O-Ne-Mg-Rich Ejecta in the Galactic Supernova Remnant Puppis A. https://doi.org/10.1088/0004-637x%2F714%2F2%2F1725

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