Observation of a New Narrow Charmonium State in Exclusive B+-->K+ pi+pi- J/psi Decays
arXiv:hep-ex/0308029 · doi:10.1103/PhysRevLett.91.262001
Abstract
We report the first observation of a narrow charmmonium state produced in the exclusive decay process B+->K+ pi+pi- J/psi. This state, which decays into pi+pi-J/psi, has a mass of 3871.8+-0.7(stat)+-0.4(syst) MeV, which is very near the M_D + M_D* mass threshold. The results are based on an analysis of 152M BBbar events collected at the Upsilon(4S) resonance in the Belle detector at the KEKB collider.
9 pages, 4 figures, contributed paper to the XXI International Symposium on Lepton and Photon Interactions at High Energies, Fermilab Aug 11-16,2003