Classifying the compact object in the unusual X-ray binary CI Cam

CI Cam is a unique Xray binary that represents either a potential newevolutionary pathway towards type Ia supernovae (if it is a white dwarf), or anideal object to study accretion disk geometry at a regime where an advectiondominated flow is expected (if it is a black hole or neutron star). However,existing data cannot discriminate between these possibilities. We propose a 120ks observation of CI Cam with the primary objective of identifying the nature ofthe compact object. We will do this by 1) resolving the 6.7 Helike and 6.97Hlike Fe lines, if present 2) investigating the origin of the brightnessfluctuations in the system and 3) obtaining the deepest observation yet of thefaint soft component in order to constrain appropriate physical models. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]