천문학논총 (Publications of The Korean Astronomical Society)

  • 제30권2호
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  • Pages.417-421
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  • 2015
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  • 1225-1534(pISSN)
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  • 2287-6936(eISSN)
한국천문학회 (The Korean Astronomical Society)
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NOVEL PICTURE OF THE AGN CENTRAL ENGINE ESTABLISHED BY X-RAY AND OPTICAL SIMULTANEOUS STUDIES

  • NODA, HIROFUMI (Nishina center, The institute of Physical and Chemical Research (RIKEN))
  • 투고 : 2014.11.30
  • 심사 : 2015.06.30
  • 발행 : 2015.09.30
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초록

We analyzed 0.5-45 keV data of NGC 3227 observed by Suzaku six times between 2008 October 28 and December 2. The count-count plot between the 0.5-3 keV and 3-10 keV bands exhibits a clear break, separating the data into bright and faint phases. Applying the difference spectrum method and time-averaged spectral fits to the phase data, we found the presence of two kinds of variable primary X-rays, (1) a hard primary component with ${\Gamma}{\sim}1.7$ dominating in the faint phase and (2) a soft primary continuum with ${\Gamma}{\sim}2.4$ appearing in the bright phase, both affected by partial absorption. Considering their timing and spectral characteristics, component (1) is presumably identical to a Compton continuum in the low/hard state, while component (2) may correspond to the hard tail emission in the high/soft state, or compact-jet emission. In that case, an accretion ow onto the central super massive black hole in NGC 3227 can be interpreted to include the two different states.

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참고문헌

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