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تسجيل مستخدم جديدGlobal Distribution of Fe K alpha Lines in the Galactic Center Region Observed with the Suzaku Satellite
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We have surveyed spatial profiles of the Fe K$alpha$ 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$alpha$ line complex into three lines of Fe emissiontype{I}, Fe emissiontype{XXV} and Fe emissiontype{XXVI} K$alpha$, and obtained their spatial intensity profiles with the resolution of $sim timeform{0D.1}$. We compared the Fe emissiontype{XXV} K$alpha$ profile with a stellar mass distribution (SMD) model made from near infrared observations. The intensity profile of Fe emissiontype{XXV} K$alpha$ is nicely fitted with the SMD model in the GRXE region, while that in the GCDX region shows $3.8pm0.3$ $(timeform{0D.2}<|l|<timeform{1D.5})$ or $19pm6$ $(|l|<timeform{0D.2})$ times excess over the best-fit SMD model in the GRXE region. Thus Fe emissiontype{XXV} K$alpha$ in the GCDX is hardly explained by the same origin of the GRXE. In the case of point source origin, a new population with the extremely strong Fe emissiontype{XXV} K$alpha$ line is required. An alternative possibility is that the majority of the GCDX is truly diffuse optically thin thermal plasma.
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