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Observations of Spectral and Time Variabilities from MCG-2-58-22

Chul-Sung Choi·Tadayasu Dotani·Insu Yi·ChulHee Kim
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Abstract

We present results from analysis of the X-ray archive data of MCG-2-58-22, acquired with ROSAT from 1991 to 1993 and with ASCA from 1993 to 1997. By analyzing light curves, we find that MCG-2-58-22 shows a clear time variability in X-ray flux. The time scales of the variations range widely from about 1000 s to more than years. Among the variations, a flare-like event overlaid on the gradual flux decrease from 1979 to 1993 is detected. We also find clear time variability of the spectra in the energy range of 0.1 - 2.0 keV. However, the flux variation does not influences on their spectra in the energy range of 2 - 10 keV. The implications of these observational results are discussed in terms of a supermassive black hole model and accretion flow dynamics near the central black hole.

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Chul-Sung Choi, Tadayasu Dotani, Insu Yi, ChulHee Kim. 2000-07-14. Observations of Spectral and Time Variabilities from MCG-2-58-22. https://arxiv.org/abs/astro-ph/0007195

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