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arXiv · 1209.0067

The K-shell Line Distribution of Heavy Elements along the Galactic Plane Observed with Suzaku

Hideki Uchiyama·Masayoshi Nobukawa·Takeshi Go Tsuru·Katsuji Koyama
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Abstract

We report the global distribution of the intensities of the K-shell lines from the 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 with 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 the GCXE compared to the GRXE. Although the prominent K-shell lines are represented by $\sim$1 keV and $\sim$7 keV temperature plasmas, these two temperatures are not equal between the GCXE and GRXE. In fact, the spectral analysis of the GCXE and GRXE revealed that the $\sim$1 keV plasma in the GCXE has lower temperature than that in the GRXE, and vice versa for the $\sim$7 keV plasma.

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Hideki Uchiyama, Masayoshi Nobukawa, Takeshi Go Tsuru, Katsuji Koyama. 2012-10-10. The K-shell Line Distribution of Heavy Elements along the Galactic Plane Observed with Suzaku. https://doi.org/10.1093/pasj%2F65.1.19

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