A new method for selecting exclusive semileptonic charmless B-decays at e+e− colliders at the ϒ(4S)

We introduce a new method for selecting exclusive semileptonic charmless B-decays in the presence of a large background. The method can be applied to charged and neutral B-mesons decaying into any exclusive semileptonic final state. The method is designed for high luminosity e+e− colliders operating at the ϒ(4S). It employs an improved partial reconstruction technique for D*-mesons and a novel 0-C event fit to both B-mesonʹs decay products resulting in the kinematics of all particles (including neutrinos) in the event. The charged lepton energies are accessible from 1.0 GeV to the kinematic limit.