Further Experimental Studies of Two - Body Radiative Υ Decays
نویسندگان
چکیده
Continuing our studies of radiative Υ decays, we report on a search for Υ → γη and Υ → γfJ(2220) in 61.3 pb of ee data taken with the CLEO II detector at the Cornell Electron Storage Ring. For the γη search the three decays of the η meson to πππ, πππ, and γγ were investigated. We found no candidate events in the (3π) modes and no significant excess over expected backgrounds in the γγ mode to set a limit on the branching fraction of B(Υ → γη)<2.1×10−5 at 90% C.L. The three charged two-body final states hh (h = π,K, p) were investigated for fJ(2220) production, with one, one, and two events found, respectively. Limits at 90% C.L. of B(Υ → γfJ) × B(fJ → hh) ∼ 1.5× 10 have been set for each of these modes. We compare our results to measurements of other radiative Υ decays, to measurements of radiative J/ψ decays, and to theoretical predictions.
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تاریخ انتشار 2002