2011/11/25 by Hideki Uchiyama, Masayoshi Nobukawa, Takeshi Go Tsuru +2 · 3 citations
Physics and Astronomy · #Astrophysical Phenomena and Observations #Astrophysics and Cosmic Phenomena #Astrophysics and Star Formation Studies
paper · pdf · doi:10.1093/pasj/63.sp3.s903
Abstract We surveyed spatial profiles of the Fe K α lines in the Galactic center diffuse X-rays (GCDX), including the transient region from the GCDX to the Galactic ridge X-ray emission (GRXE), with the Suzaku satellite. We resolved Fe K α line complex into three lines of Fe I, Fe XXV, and Fe XXVI K α , and obtained their spatial intensity profiles with a resolution of ∼ 0 ^∘ . 1. We compared the Fe XXV K α profile with a stellar mass distribution (SMD) model made from near infrared observations. The intensity profile of Fe XXV K α was nicely fitted with the SMD model in the GRXE region, while that in the GCDX region showed a 3.8 ± 0.3 (0 ^∘ . 2 <\vert l\vert< 1 ^∘ . 5) or 19 ± 6 ( \vert l\vert< 0 ^∘ . 2) times excess over the best-fit SMD model in the GRXE region. Thus, Fe XXV K α in the GCDX is hardly explained by the same origin of the GRXE. In the case of a point-source origin, a new population with the extremely strong Fe XXV K α line is required. An alternative possibility is that the majority of the GCDX is truly diffuse optically thin thermal plasma.