We observe signals for the decays ψ(3770)→XJ/ψ from data acquired with the CLEO detector operating at the CESR e+e- collider with s=3773MeV. We measure the following branching fractions B(ψ(3770)→XJ/ ψ) and significances: (189±20±20)×10-5 (11.6σ) for X=π+π-, (80±25±16)×10-5 (3.4σ) for X=π0π0, and (87±33±22)×10-5 (3.5σ) for X=η, where the errors are statistical and systematic, respectively. The radiative return process e+e-→γψ(2S) populates the same event sample and is used to measure Γee[ψ(2S)]=(2.54±0.03±0.11)keV.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)