Observation of the Exclusive Reaction e+e- -> phi eta at sqrts=10.58 GeV

الأصل · EN

We report the observation of +e-→ ϕη near √s = 10.58 GeV with 6.5 σ significance in the K+K-γγ final state in a data sample of 224 fb⁻¹ collected by the BaBar experiment at the PEP-II e+e- storage rings. We measure the restricted radiation-corrected cross section to be σ(+e- → ϕη) =2.1± 0.4 (stat)± 0.1(syst) fb within the range |θ*| < 0.8, where θ* is the center-of-mass polar angle of the ϕ meson. The ϕ meson is required to be in the invariant mass range of 1.008 < mϕ < 1.035. The radiation-corrected cross section in the full θ* range is extrapolated to be 2.9± 0.5 (stat)± 0.1(syst) fb.