Discoveries of Diffuse Iron Line Sources from the Sgr B Region
Maeda, Yoshitomo; Koyama, Katsuji; Matsumoto, Hironori; Tsuru, Takeshi Go; Murakami, Hiroshi; Soong, Yang; Yamauchi, Shigeo; Hyodo, Yoshiaki; Inui, Tatsuya; Chan, Kai-Wing; Kissel, Steven E.
Japan, United States
Abstract
The radio complex Sgr B region was observed with the X-ray Imaging Spectrometer (XIS) on board Suzaku. This region exhibits diffuse iron lines at 6.4, 6.7, and 6.9keV, which are Kα lines of Fe I (neutral iron), Fe XXV (He-like iron), and Fe XXVI (H-like iron), respectively. The high energy resolving power of the XIS provided separate maps of the K-shell transition lines from Fe I (6.4keV) and Fe XXV (6.7keV). Although the 6.7keV line is smoothly distributed over the Sgr B region, a local excess is found near (l, b) = (0.°61,0.°01), possibly due to a new SNR. The plasma temperature is kT∼ 3 keV and the age is estimated to be younger than 7 × 103 yr. The 6.4keV image is clumpy with local excesses near Sgr B2 and at (l, b) = (0.°74,-0.°09). Like Sgr B2, this excess may be another candidate of an X-ray reflection nebula.