We report on a search for the recently reported X(3872) state using 15.1 fb -1 of e + e - data taken in the √s = 9.46-11.30 GeV region. Separate searches for the production of the X(3872) in untagged γγ fusion and e +e - annihilation following initial state radiation are made by taking advantage of the unique angular correlation between the leptons from the decay J/ψ → l + l - in X(3872) decay to π + π - J/ψ. No signals are observed in either case, and 90% confidence upper limits are established as (2J + 1)Γ γγ(X(3872))B(X → π + π - J/ψ) < 12.9 eV and Γ ee(X(3872))B(X → π + π - J/ψ)< 8.3 eV.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)