Refine
Language
- English (261)
Has Fulltext
- yes (261)
Is part of the Bibliography
- no (261)
Keywords
- e +-e − Experiments (14)
- BESIII (13)
- Branching fraction (9)
- Particle and Resonance Production (7)
- Spectroscopy (6)
- Charm Physics (5)
- Quarkonium (5)
- Exotics (4)
- Lepton colliders (4)
- Charmed mesons (3)
Institute
- Physik (259)
The Born cross section of the process e+e−→ηJ/ψ at a center-of-mass energy s√=3.773 GeV is measured to be (8.89±0.88±0.42) pb, using a data sample collected with the BESIII detector operating at the BEPCII storage ring. The decay ψ(3770)→ηJ/ψ is observed for the first time with a statistical significance of 7.4σ. From a fit to the dressed cross-section line-shape of e+e−→ηJ/ψ from s√=3.773 to 4.600 GeV we obtain the branching fraction of the decay ψ(3770)→ηJ/ψ to be (11.6±6.1±1.0)×10−4 when the ψ(3770) decay amplitude is added coherently to the other contributions, and (7.9±1.0±0.7)×10−4 when it is added incoherently. Here the first uncertainties are statistical and the second are systematic.