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تسجيل مستخدم جديدNGC 2992 in an X-ray high state observed by XMM: Response of the Relativistic Fe K$alpha$ Line to the Continuum
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X. W. Shu
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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$alpha$ 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$alpha$ 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$alpha$ line does not respond to variability in the X-ray.
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