RADIATIVE UPSILON (1S) DECAYS

We report on a study of exclusive radiative decays of the {Upsilon}(1{ital S}) resonance. We have considered decays into final states of the form {Upsilon}{r arrow}{gamma}{ital n}({ital h}{sup +}{ital h}{sup {minus}}), with ({ital h}{sup +}{ital h}{sup {minus}}) denoting a charged-hadron pair (either {pi}{sup +}{pi}{sup {minus}},{ital K}{sup +}{ital K}{sup {minus}}, or {ital p{bar p}}), and {ital n} denoting the number of such pairs in the event. We measure branching ratios for {ital n}=2, 3, and 4, and search for structure in the recoiling hadronic system. For the {ital n}=1 case, we present upper limits. No evidence is observed for two-body radiative decays of the {Upsilon}(1{ital S}) meson in any of the above channels.