Kinematic Fit for the Radiative Bhabha Calibration of BaBar's   Electromagnetic Calorimeter
  For the radiative Bhabha calibration of BaBar's electromagnetic calorimeter, the measured energy of a photon cluster is being compared with the energy obtained via a kinematic fit involving other quantities from that event. The details of the fitting algorithm are described in this note, together with its derivation and checks that ensure that the fitting routine is working properly. 
Johannes M. Bauer