title: Resummed photon spectrum in radiative upsilon decays.
abstract: We present a theoretical prediction for the photon spectrum in radiative upsilon decay including the effects of resumming the end point region, E(gamma)-->M(upsilon)/2. Our approach is based on nonrelativistic QCD (NRQCD) and the soft-collinear effective theory. We find that our results give much better agreement with data than the leading order NRQCD prediction.
authors.affiliation: Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA.
authors.forename: Sean
authors.initials: S
authors.lastname: Fleming
authors.forename: Adam K
authors.initials: AK
authors.lastname: Leibovich