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arXiv · 1805.12149

Tracking the Iron K$\alpha$ line and the Ultra Fast Outflow in NGC 2992 at different accretion states

A. Marinucci·S. Bianchi·V. Braito·G. Matt·E. Nardini·J. Reeves
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Abstract

The Seyfert 2 galaxy NGC 2992 has been monitored eight times by XMM-Newton in 2010 and then observed again in 2013, while in 2015 it was simultaneously targeted by Swift and NuSTAR. XMM-Newton always caught the source in a faint state (2-10 keV fluxes ranging from 0.3 to 1.6$\times10^{-11}$ erg cm$^{-2}$ s$^{-1}$) but NuSTAR showed an increase in the 2-10 keV flux up to 6$\times10^{-11}$ erg cm$^{-2}$ s$^{-1}$. We find possible evidence of an Ultra Fast Outflow with velocity $v_1=0.21\pm0.01c$ (detected at about 99% confidence level) in such a flux state. The UFO in NGC 2992 is consistent with being ejected at a few tens of gravitational radii only at accretion rates greater than 2% of the Eddington luminosity. The analysis of the low flux 2010/2013 XMM data allowed us to determine that the Iron K$\alpha$ emission line complex in this object is likely the sum of three distinct components: a constant, narrow one due to reflection from cold, distant material (likely the molecular torus); a narrow, but variable one which is more intense in brighter observations and a broad relativistic one emitted in the innermost regions of the accretion disk, which has been detected only in the 2003 XMM observation.

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A. Marinucci, S. Bianchi, V. Braito, G. Matt, E. Nardini, J. Reeves. 2018-05-30. Tracking the Iron K$\alpha$ line and the Ultra Fast Outflow in NGC 2992 at different accretion states. https://doi.org/10.1093/mnras%2Fsty1436

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