What is on the black hole menu Joint HST/COS and XMM/EPIC spectroscopy of the X

We request 12 HST orbits of the HMXB M33 X7, to secure COS spectroscopy. M33X7 is a strong source of Xrays which influence the donor star wind and affectits dynamics. Therefore, we request 25 ks of XMM time to obtain Xrayspectroscopy simultaneously with the UV observations, to be performed at threekey orbital phases, tracing the BH eclipse, egress, and inferior conjunction.From the eclipse spectrum we will measure the wind velocity and massloss rateof the donor star. Realistic wind parameters are needed to develop the models ofmassive binary evolution towards binary BHs. Coordinated UV and Xraymeasurements in eclipse and egress will describe the gas flows towards the BHand establish its accretion efficiency, probing the theories of accretion onto a BH. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]