Resummed photon spectrum in radiative upsilon decays.
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.
Fleming
Sean
S
Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA.
Leibovich
Adam K
AK