Discovery of recombining plasma associated with the candidate supernova remnant G189.6+3.3 with Suzaku

Shigeo Yamauchi; Moe Oya; Kumiko K. Nobukawa; Thomas G. Pannuti

doi:10.1093/pasj/psaa070

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arXiv · 2007.03226

Discovery of recombining plasma associated with the candidate supernova remnant G189.6+3.3 with Suzaku

Shigeo Yamauchi·Moe Oya·Kumiko K. Nobukawa·Thomas G. Pannuti

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Abstract

We present the results of an X-ray spectral analysis of the northeast region of the candidate supernova remnant G189.6+3.3 with Suzaku. K-shell lines from highly ionized Ne, Mg, Si, and S were detected in the spectrum for the first time. In addition, a radiative recombining continuum (RRC) from He-like Si was clearly seen near 2.5 keV. This detection of an RRC reveals for the first time that G189.6+3.3 possesses an X-ray-emitting recombining plasma (RP). The extracted X-ray spectrum in the 0.6-10.0 keV energy band is well fitted with a model consisting of a collisional ionization equilibrium plasma component (associated with the interstellar medium) and an RP component (associated with the ejecta). The spectral feature shows that G189.6+3.3 is most likely to be a middle-aged SNR with an RP.

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Shigeo Yamauchi, Moe Oya, Kumiko K. Nobukawa, Thomas G. Pannuti. 2020-07-07. Discovery of recombining plasma associated with the candidate supernova remnant G189.6+3.3 with Suzaku. https://doi.org/10.1093/pasj%2Fpsaa070

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