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arXiv · 1902.08386

X-ray spectra of Sgr A East and diffuse X-ray background near the Galactic center

Akiko Ono·Hideki Uchiyama·Shigeo Yamauchi·Masayoshi Nobukawa·Kumiko K. Nobukawa·Katsuji Koyama
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Abstract

This paper reports the analysis procedure and results of simultaneous spectral fits of the Suzaku archive data for Sagittarius (Sgr) A East and the nearby Galactic center X-ray emission (GCXE). The results are that the mixed-morphology supernova remnant Sgr A East has a recombining plasma (RP) with Cr and Mn He$α$ lines, and a power-law component (PL) with an Fe I K$α$ line. The nearby GCXE has a $\sim$1.5-times larger surface brightness than the mean GCXE far from Sgr A East, although the spectral shape is almost identical. Based on these results, we interpret that the origins of the RP and the PL with the Fe I K$α$ line are past big flares of Sgr A$^*$.

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Akiko Ono, Hideki Uchiyama, Shigeo Yamauchi, Masayoshi Nobukawa, Kumiko K. Nobukawa, Katsuji Koyama. 2019-02-22. X-ray spectra of Sgr A East and diffuse X-ray background near the Galactic center. https://doi.org/10.1093/pasj%2Fpsz025

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