# NEW EVIDENCE FOR HIGH ACTIVITY OF THE SUPERMASSIVE BLACK HOLE IN OUR GALAXY

@article{Nobukawa2011NEWEF,
title={NEW EVIDENCE FOR HIGH ACTIVITY OF THE SUPERMASSIVE BLACK HOLE IN OUR GALAXY},
author={Masayoshi Nobukawa and Syukyo Gando Ryu and Takeshi Go Tsuru and Katsuji Koyama},
journal={The Astrophysical Journal},
year={2011},
volume={739}
}
Prominent K-shell emission lines of neutral iron (hereafter Fe I-K lines) and hard-continuum X-rays from molecular clouds (MCs) in the Sagittarius B (Sgr B) region were found in two separate Suzaku observations in 2005 and 2009. The X-ray flux of the Fe I-K lines decreased in correlation with the hard-continuum flux by a factor of 0.4-0.5 in four years, which is almost equal to the light traveling across the MCs. The rapid and correlated time variability, the equivalent width of the Fe I-K… Expand

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