A new powerful and highly variable disc wind in an AGN–star-forming galaxy, the case of MCG-03-58-007

We present the discovery of a new candidate for a fast disk wind, in the nearby Seyfert 2 galaxy MCG-03-58-007. This wind is discovered in a deep Suzaku observation that was performed in 2010. Overall the X-ray spectrum of MCG-03-58-007 is highly absorbed by a neutral column density of NH~10^23 cm^-2, in agreement with the optical classification as a type 2 AGN. In addition, this observation unveiled the presence of two deep absorption troughs at E = 7.4 +- 0.1 keV and E = 8.5 +- 0.2 keV. If associated with blue-shifted FeXXVI, these features can be explained with the presence of two highly ionised (log \xi/(erg cm/s)~ 5.5) and high column density (NH~5-8 x 10^23cm^-2) outflowing absorbers with v_out1~ -0.1c and v_out2~ -0.2c. The disk wind detected during this observation is most likely launched from within a few hundreds gravitational radii from the central black and has a kinetic output that matches the prescription for significant feedback. The presence of the lower velocity component of the disk wind is independently confirmed by the analysis of a follow-up XMM-Newton & NuSTAR observation. A faster (v_out~ -0.35 c) component of the wind is also seen in this second observation. During this observation we also witnessed an occultation event lasting \Delta t ~ 120 ksec, which we ascribe to an increase of the opacity of the disk wind (\Delta NH~1.4x10^24 cm^-2). Our interpretation is that the slow zone (v_out~ -0.1c) of the wind is the most stable but inhomogeneous component, while the faster zones could be associated with two different inner streamlines of the wind.