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Variation of the broad X-ray iron line in MCG-6-30-15 during a flare

K. Iwasawa·A. C. Fabian·A. J. Young·H. Inoue·C. Matsumoto
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Abstract

We report results on the broad iron emission line of the Seyfert galaxy MCG-6-30-15, obtained from the second long ASCA observation in 1997. The time-averaged profile of the broad line is very similar to that seen with ASCA in 1994, so confirming the detailed model fit then obtained. A bright flare is seen in the light curve, during which the continuum was soft. At that time the emission line peaks around 5 keV and most of its emission is shifted below 6 keV with no component detected at 6.4 keV (EW<60 eV). This can be interpreted as the result of an extraordinarily large gravitational redshift due to a dominant flare occurring very close to the black hole at a radius of <5m.

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K. Iwasawa, A. C. Fabian, A. J. Young, H. Inoue, C. Matsumoto. 1999-04-07. Variation of the broad X-ray iron line in MCG-6-30-15 during a flare. https://doi.org/10.1046/j.1365-8711.1999.02671.x

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