Observation of X(3872) -> J/psi gamma and Search for X(3872) -> psi 'gamma in B Decays

Abstract

We report a study of B J=c K and B c K decay modes using 772 10 B B events collected at the 4S resonance with the Belle detector at the KEKB energy-asymmetric eecollider. We observe X3872 J=c and report the first evidence for J=c in B decays, while in a search for X3872 c significant signal is found. We measure the branching fractions