Chandra observations of diffuse X-rays from the Sagittarius B2 cloud

被引:82
作者
Murakami, H [1 ]
Koyama, K
Maeda, Y
机构
[1] Kyoto Univ, Grad Sch Sci, Dept Phys, Sakyo Ku, Kyoto 6068502, Japan
[2] Penn State Univ, Dept Astron & Astrophys, Davey Lab 525, University Pk, PA 16802 USA
关键词
Galaxy : center; ISM : clouds; ISM : individual (Sagittarius B2); X-rays : individual (Sagittarius B2); X-rays : ISM;
D O I
10.1086/322282
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
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 photoelectric absorption at low energy. The absorption-corrected X-ray luminosity is similar to 1 x 10(35) ergs s(-1), 2 orders of magnitude larger than the integrated luminosity of all the resolved point sources. The diffuse X-rays come mainly from the southwest 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.
引用
收藏
页码:687 / 692
页数:6
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