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Chandra Observations of Diffuse X-Rays from the Sagittarius B2 Cloud

H. Murakami·K. Koyama·Y. Maeda
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Abstract

We present the first Chandra results of the giant molecular cloud Sagittarius B2 (Sgr B2), located about 100 pc away from the Galactic center. Diffuse X-rays are clearly separated from one-and-a-half dozen resolved point sources. The X-ray spectrum exhibits pronounced iron K-shell transition lines at 6.40 keV (K alpha) and 7.06 keV (K beta), deep iron K-edge at 7.11 keV and large photo-electric absorption at low energy. The absorption-corrected X-ray luminosity is \sim 1 times 10^{35} erg s^{-1}, two orders of magnitude larger than the integrated luminosity of all the resolved point sources. The diffuse X-rays come mainly from the south-west half of the cloud with a concave-shape pointing to the Galactic center direction. These results strongly support the ASCA model that Sgr B2 is irradiated by an X-ray source at the Galactic center side.

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H. Murakami, K. Koyama, Y. Maeda. 2001-05-16. Chandra Observations of Diffuse X-Rays from the Sagittarius B2 Cloud. https://doi.org/10.1086/322282

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