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Slow Temperature Equilibration Behind the Shock Front of SN 1006

Jacco Vink·J. Martin Laming·Ming Feng Gu·Andrew Rasmussen·Jelle S. Kaastra
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Abstract

We report on the observation of OVII Doppler line broadening in a compact knot at the edge of SN 1006 detected with the Reflective Grating Spectrometer on board XMM-Newton. The observed line width of sigma = 3.4+/-0.5 eV at a line energy of 574 eV indicates an oxygen temperature of kT = 528+/-150 keV. Combined with the observed electron temperature of 1.5 keV the observed broadening is direct evidence for temperature non-equilibration in high Mach number shocks, and slow subsequent equilibration. The OVII line emission allows an accurate determination of the ionization state of the plasma, which is characterized by a relatively high forbidden line contribution, indicating log(n_e t) ~ 9.2.

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Jacco Vink, J. Martin Laming, Ming Feng Gu, Andrew Rasmussen, Jelle S. Kaastra. 2003-03-03. Slow Temperature Equilibration Behind the Shock Front of SN 1006. https://doi.org/10.1086/375125

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