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Observation of the Decay Omega_C^0 --> Omega- e+ nu_e

R. Ammar·CLEO Collaboration
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Abstract

Using the CLEO detector at the Cornell Electron Storage Ring, we have observed the Omega_c (css ground state) in the decay Omega_c -> Omega- e+ nu. We find a signal of 11.4 +- 3.8 (stat) events. The probability that we have observed a background fluctuation is 7.6 x 10-5. We measure BF(Omega_c -> Omega- e+ nu) x sigma(e+ e- -> Omega_c X) = (42.2 +- 14.1 (stat) +- 5.7 (syst)) fb and R = Gamma(Omega_c -> Omega- pi+)/Gamma(Omega_c -> Omega- e+ nu) = 0.41 +- 0.19 (stat) +- 0.04 (syst). This is the first statistically significant observation of an individual decay mode of the Omega_c in e+ e- annhiliation, and the first example of a baryon decaying via beta-emmision, where no quarks from the first generation participate in the reaction.

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R. Ammar, CLEO Collaboration. 2002-07-25. Observation of the Decay Omega_C^0 --> Omega- e+ nu_e. https://doi.org/10.1103/physrevlett.89.171803

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