Journal of The Korean Astronomical Society (천문학회지)

The Korean Astronomical Society (한국천문학회)
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A SPECTROSCOPIC STUDY OF THE SEYFERT GALAXY MCG-2-58-22

  • Choi, Chul-Sung (Korea Astronomy and Space Science Institute) ;
  • Dotani, Tadayasu (Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency) ;
  • Chang, Heon-Young (Department of Astronomy and Atmospheric Sciences, Kyungpook National Univ.)
  • Published : 2005.09.01
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Abstract

We present analysis results of the energy spectra of MCG-2-58-22 associated with occasional flares which appear in a long-term X-ray light curve. We measure an intrinsic power-law slope of this object to be ${\Gamma}=1.74{\pm}0.02$ in the energy range of ${\sim}1-5keV$ and find that this slope is little affected by flares. We confirm that there exists a broad excess emission above 5 keV to the power-law continuum. The excess emission is less variable compared with a flux variation of flare and tends to be relatively weak during flares. A soft X-ray spectrum is also found to change, implying the presence of a variable soft component. We discuss the implications of these spectral variations.

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References

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