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Chandra LETG Observations of Supernova Remnant 1987A

Svetozar A. Zhekov·Richard McCray·Kazimierz J. Borkowski·David N. Burrows·Sangwook Park
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Abstract

We discuss the results from deep Chandra LETG observations of the supernova remnant 1987A (SNR 1987A). We find that a distribution of shocks, spanning the same range of velocities (from 300 to 1700 km/s) as deduced in the first part of our analysis (Zhekov et al. 2005, ApJL, 628, L127), can account for the entire X-ray spectrum of this object. The post-shock temperature distribution is bimodal, peaking at kT 0.5 and 3 keV. Abundances inferred from the X-ray spectrum have values similar to those for the inner circumstellar ring, except that the abundances of nitrogen and oxygen are approximately a factor of two lower than those inferred from the optical/UV spectrum. The velocity of the X-ray emitting plasma has decreased since 1999, apparently because the blast wave has entered the main body of the inner circumstellar ring.

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Svetozar A. Zhekov, Richard McCray, Kazimierz J. Borkowski, David N. Burrows, Sangwook Park. 2006-03-13. Chandra LETG Observations of Supernova Remnant 1987A. https://doi.org/10.1086/504285

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