The Resummed Photon Spectrum in Radiative Upsilon Decays
arXiv:hep-ph/0211303 · doi:10.1103/PhysRevLett.90.032001
Abstract
We present a theoretical prediction for the photon spectrum in radiative Upsilon decay including the effects of resumming the endpoint region, E_γ-> M_Υ/2. Our approach is based on NRQCD and the soft collinear effective theory. We find that our results give much better agreement with data than the leading order NRQCD prediction.
4 pages, 6 figures