2013/02/25 by Hideki Uchiyama, Masayoshi Nobukawa, Takeshi Go tsuru +1 · 6 citations
Physics and Astronomy · #Solar and Space Plasma Dynamics #Astrophysical Phenomena and Observations #Astrophysics and Cosmic Phenomena
paper · pdf · doi:10.1093/pasj/65.1.19
We report on the global distribution of the intensities of the K-shell lines from He-like and H-like ions of S, Ar, Ca, and Fe along the Galactic plane. From the profiles, we clearly separate the Galactic center X-ray emission (GCXE) and the Galactic ridge X-ray emission (GRXE). The intensity profiles of the He-like K α lines of S, Ar, Ca, and Fe along the Galactic plane are approximately similar to each other, while not for the H-like Ly α lines. In particular, the profiles of H-like Ly α of S and Fe show remarkable contrast: a large excess of Fe, and almost no excess of S lines in GCXE compared to GRXE. Although the prominent K-shell lines are represented by ∼ 1 keV and ∼ 7 keV temperature plasmas, these two temperatures are not equal between GCXE and GRXE. In fact, a spectral analysis of GCXE and GRXE revealed that the ∼ 1 keV plasma in GCXE has a lower temperature than that in GRXE, and vice versa for the ∼ 7 keV plasma.