2001/05/16 by H. Murakami, Hiroshi Murakami, K. Koyama +3 · 3 citations
Physics and Astronomy · #Astrophysical Phenomena and Observations #Astrophysics and Star Formation Studies #Galaxies: Formation, Evolution, Phenomena #astro-ph
paper · pdf · doi:10.1086/322282
11 pages, 3 figures, to be published in ApJ
arxiv created 2001/05/16 · openalex publication_date 2001/09/10 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/31
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 (Kα) and 7.06 keV (Kβ), deep iron K-edge at 7.11 keV, and large photoelectric absorption at low energy. The absorption-corrected X-ray luminosity is ~1 × 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.