Oscillation physics with neutrino beams from electron capture

We present the physics potential of a flavor pure electron neutrino beam coming from electron capture processes directed towards a megaton water cherenkov detector. In the rest frame of the processes the energy of the neutrinos is monochromatic. We discuss the potential to resolve correlations and degeneracies in the search for sin2 2θ13 and δCP of this scenario at low and high gamma. At low gamma the neutrino beam can be viewed as monochromatic at the detector and a measurement in different settings of gamma is required. At high gamma the energy of the neutrinos at the detector depends on the distance from the beam center and energy reconstruction is accurately possible by the position measurement within the detector. (orig.)