ISSN - 15507998, Physical Review D - Particles, Fields, Gravitation and Cosmology, 2010, vol. 81, p. -
Observation of inclusive D*± production in the decay of Υ(1S)
We present a study of the inclusive D*± production in the decay of Υ(1S) using (98.6±0.9)×106 Υ(2S) mesons collected with the BABAR detector at the Υ(2S) resonance. Using the decay chain Υ(2S)→π+π-Υ(1S), Υ(1S)→D*±X, where X is unobserved, we measure the branching fraction B[Υ(1S)→D*±X]=(2. 52±0.13(stat)±0.15(syst))% and the D*± momentum distribution in the rest frame of the Υ(1S). We find evidence for an excess of D*± production over the expected rate from the virtual photon annihilation process Υ(1S)→γ *→cc̄→D*±X. © 2010 The American Physical Society.