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arXiv · 1208.5560

Evidence for Recombining Plasma in the Supernova Remnant G346.6-0.2

Shigeo Yamauchi·Masayoshi Nobukawa·Katsuji Koyama·Manami Yonemori
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Abstract

We present the Suzaku results of the supernova remnant (SNR) G346.6-0.2. The X-ray emission has a center-filled morphology with the size of 6' x 8' within the radio shell. Neither an ionization equilibrium nor non-equilibrium (ionizing) plasma can reproduce the spectra remaining shoulder-like residuals in the 2-4 keV band. These structures are possibly due to recombination of free electrons to the K-shell of He-like Si and S. The X-ray spectra are well fitted with a plasma model in a recombination dominant phase. We propose that the plasma was in nearly full ionized state at high temperature of 5 keV, then the plasma changed to a recombining phase due to selective cooling of electrons to lower temperature of 0.3 keV. G346.6-0.2 would be in an epoch of the recombining phase.

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Shigeo Yamauchi, Masayoshi Nobukawa, Katsuji Koyama, Manami Yonemori. 2012-08-28. Evidence for Recombining Plasma in the Supernova Remnant G346.6-0.2. https://doi.org/10.1093/pasj%2F65.1.6

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