Discoveries of Diffuse Iron Line Sources from the Sgr B Region

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 6.9 keV, 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 (6.4 keV) and Fe XXV (6.7 keV). Although the 6.7 keV 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 6.4 keV 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.