Discovery of ultra-fast outflows with vout > 0.3c in local, bright AGN

Ultra-fast outflows are highly ionized thick winds with characteristic absorption features (FeXXV and FeXXVI at 6.67-6.97 keV rest-frame) in the hard X-ray band, strongly blue-shifted by the extreme outflow velocities. These quasi-relativistic winds are thought to be the most promising mechanism powering AGN feedback, influencing the SMBH/host galaxy co-evolution. Assessing the relation between UFO velocity and AGN power, and the maximum velocity achievable by UFOs, is crucial to determine the launching mechanism of nuclear winds (i.e., radiation vs. magnetic driving). While few high-z luminous QSOs do show UFOs with velocities up to 0.4-0.6c, in the local Universe we have been limited so far by the background noise, shaping the canonical band limit of 10 keV, corresponding to a maximum velocity detectable of ~0.2c. We will present the first systematic XMM study on 33 bright sources to search for UFOs in the 7-12 keV band. Particular care has been dedicated to assessing the impact of the background with three different techniques employed. Our extension to E>10 keV in the search for UFOs has led to the detection of four previously unknown UFOs with very high velocities (v>0.3c), confirming that local Seyferts do show such high velocity UFOs. Discovering high-energy UFOs at low redshift and luminosity will influence our current knowledge on the linear correlation between bolometric luminosity of AGN and the outflow velocity of the winds.