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arXiv · 1509.00214

New Identification of the Mixed-Morphology Supernova Remnant G298.6-0.0 with Possible Gamma-ray Association

Aya Bamba·Makoto Sawada·Yuto Nakano·Yukikatsu Terada·John Hewitt·Robert Petre·Lorella Angelini
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Abstract

We present an X-ray analysis on the Galactic supernova remnant (SNR) G298.6-0.0 with Suzaku. The X-ray image shows a center-filled structure inside the radio shell, implying this SNR is categorized as a mixed-morphology (MM) SNR. The spectrum is well reproduced by a single temperature plasma model in ionization equilibrium, with a temperature of 0.78 (0.70-0.87) keV. The total plasma mass of 30 solar mass indicates that the plasma has interstellar medium origin. The association with a GeV gamma-ray source 3FGL J1214.0-6236 on the shell of the SNR is discussed, in comparison with other MM SNRs with GeV gamma-ray associations. It is found that the flux ratio between absorption-corrected thermal X-rays and GeV gamma-rays decreases as the MM SNRs evolve to larger physical sizes. The absorption-corrected X-ray flux of G298.6-0.0 and the GeV gamma-ray flux of 3FGL J1214.0-6236 closely follow this trend, implying that 3FGL J1214.0-6236 is likely to be the GeV counterpart of G298.6-0.0.

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Aya Bamba, Makoto Sawada, Yuto Nakano, Yukikatsu Terada, John Hewitt, Robert Petre, Lorella Angelini. 2015-09-01. New Identification of the Mixed-Morphology Supernova Remnant G298.6-0.0 with Possible Gamma-ray Association. https://doi.org/10.1093/pasj%2Fpsv096

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