Observation of a Broad Structure in the π+π-J/ψ Mass Spectrum around 4.26 GeV/c2
Abstract
We study initial-state radiation events, e+e-→γISRπ+π-J/ψ, with data collected with the BABAR detector. We observe an accumulation of events near 4.26GeV/c2 in the invariant-mass spectrum of π+π-J/ψ. Fits to the mass spectrum indicate that a broad resonance with a mass of about 4.26GeV/c2 is required to describe the observed structure. The presence of additional narrow resonances cannot be excluded. The fitted width of the broad resonance is 50 to 90MeV/c2, depending on the fit hypothesis.
- Publication:
-
Physical Review Letters
- Pub Date:
- September 2005
- DOI:
- 10.1103/PhysRevLett.95.142001
- arXiv:
- arXiv:hep-ex/0506081
- Bibcode:
- 2005PhRvL..95n2001A
- Keywords:
-
- 14.40.Gx;
- 13.25.Gv;
- 13.66.Bc;
- Mesons with S=C=B=0 mass>2.5 GeV;
- Decays of J/psi Upsilon and other quarkonia;
- Hadron production in e<sup>-</sup>e<sup>+</sup> interactions;
- High Energy Physics - Experiment
- E-Print:
- 7 pages, 3 postscript figues, 0 tables submitted to Physics Review Letter