The remarkable disk wind in IZw 1

IZw 1 is the prototype narrow line Seyfert 1 galaxy; with a bolometric luminosity of 3x10⁴⁵ erg s^-1 and an estimated black hole mass of 3x10⁷ M_SUN, it implies that IZw 1 accretes at close to the Eddington limit. Such high accretion rate AGN are prime candidates for driving a fast disk wind. Indeed past XMM-Newton observations of IZw 1 revealed the presence of a broad, blueshifted P-Cygni profile with a broadened emission from ionized iron near 7 keV and a blue-shifted absorption at 9 keV likely originating from a wide angle wind outflowing at ~0.25c. I will present the results of the new simultaneous XMM & NuSTAR observations of IZw 1 that were performed in 2020. These new observations confirm the presence of the powerful wind with a kinetic power on average of ~10% of the Eddington luminosity. The new observations also unveiled a remarkable variability of the disk wind, which appears to respond to the extremely variable primary emission. A multi-epoch modelling of the past X-ray observations of IZw 1 with latest state of the art disk wind model will also be presented.