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arXiv · 1003.1789

NGC 2992 in an X-ray high state observed by XMM: Response of the Relativistic Fe K$α$ Line to the Continuum

X. W. Shu·T. Yaqoob·K. D. Murphy·V. Braito·J. X. Wang·W. Zheng
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Abstract

We present the analysis of an XMM observation of the Seyfert galaxy NGC 2992. The source was found in its highest level of X-ray activity yet detected, a factor $\sim 23.5$ higher in 2--10 keV flux than the historical minimum. NGC 2992 is known to exhibit X-ray flaring activity on timescales of days to weeks, and the XMM data provide at least factor of $\sim 3$ better spectral resolution in the Fe K band than any previously measured flaring X-ray state. We find that there is a broad feature in the \sim 5-7 keV band which could be interpreted as a relativistic Fe K$α$ emission line. Its flux appears to have increased in tandem with the 2--10 keV continuum when compared to a previous Suzaku observation when the continuum was a factor of $\sim 8$ lower than that during the XMM observation. The XMM data are consistent with the general picture that increased X-ray activity and corresponding changes in the Fe K$α$ line emission occur in the innermost regions of the putative accretion disk. This behavior contrasts with the behavior of other AGN in which the Fe K$α$ line does not respond to variability in the X-ray.

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X. W. Shu, T. Yaqoob, K. D. Murphy, V. Braito, J. X. Wang, W. Zheng. 2010-03-09. NGC 2992 in an X-ray high state observed by XMM: Response of the Relativistic Fe K$α$ Line to the Continuum. https://doi.org/10.1088/0004-637x%2F713%2F2%2F1256

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