XMM-Newton observations of the enigmatic black hole candidate IGR J17091-3624

For nearly 20 years, the microquasar GRS 1915+105 was unique in the Galaxy for its powerful jets, massive winds, and exotic X-ray variability. In February 2011, IGR J17091-3624 went into outburst and began to mimic GRS 1915+105, opening a complete new window to understand accretion disk physics at Eddington rates. To progress further, GRS 1915+105 and IGR J17091--3624 need to be studied and compared in their different spectral states. We therefore propose a maximum of two ToO 40 ksec observations of IGR J17091-3624 with XMM-Newton in case the source is still active during AO12. These observations will sample spectral states not yet observed with high-resolution spectroscopy and at energies <2 keV.