0220105

We propose four 80ksec observations of the black hole candidate Cyg X-1 simultaneous to our accepted XMM-Newton observations in the fall of 2004. The scientific aim of this campaign is to measure a high signal to noise spectrum of Cyg X-1 from 0.5 to above 600keV allowing us to constrain models for the Comptonizing plasma responsible for the hard X-ray spectrum to constrain the amount of Compton reflection in the system to provide the >10keV continuum above a possibly relativistically broadened Fe Kalpha line and to search for and study the effects of non-thermal Comptonization and/or synchrotron self-Compton emission from a jet. [truncated! Please see actual data for full text]