Journal article
Observation of a narrow charmoniumlike state in exclusive [formula presented] decays
SK Choi, SL Olsen, K Abe, T Abe, I Adachi, BS Ahn, H Aihara, K Akai, M Akatsu, M Akemoto, Y Asano, T Aso, V Aulchenko, T Aushev, AM Bakich, Y Ban, S Banerjee, A Bondar, A Bozek, M Bračko Show all
Physical Review Letters | Published : 2003
Abstract
We report the observation of a narrow charmoniumlike state produced in the exclusive decay process [Formula presented]. This state, which decays into [Formula presented], has a mass of [Formula presented], a value that is very near the [Formula presented] mass threshold. The results are based on an analysis of 152M [Formula presented]-[Formula presented] events collected at the [Formula presented] resonance in the Belle detector at the KEKB collider. The signal has a statistical significance that is in excess of [Formula presented]. © 2003 The American Physical Society.