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Unusual diffuse X-ray source in the Galactic center region

Atsushi Senda·Hiroshi Murakami·Katsuji Koyama
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Abstract

We report the ASCA and Chandra discovery of a diffuse X-ray source in the Galactic center region. The X-ray spectrum is fitted with a non-equilibrium ionization (NEI) plasma model of about 6-keV temperature. The model requires higher than solar metal abundances, a young plasma age of $\simeq$ 100 years and a large N_H value of about 10^{23} cm^{-2}. The N_H value constrains the source position to be in the Galactic center region at about 8.5 kpc distance. The high resolution X-ray image with the Chandra ACIS shows a ring of 10'' radius which corresponds to 0.4 pc at the Galactic center, and a tail-like structure. Although the morphology is peculiar, the other X-ray features are likely to be a very young supernova remnant, possibly in a free expansion phase.

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Atsushi Senda, Hiroshi Murakami, Katsuji Koyama. 2001-09-30. Unusual diffuse X-ray source in the Galactic center region. https://doi.org/10.1086/324685

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