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Observation of the eta_c(2S) in exclusive B-->K KsK-pi+ decays

S. -K. Choi
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Abstract

We report the observation of a narrow peak in the KsK-pi+ invariant mass distribution in a sample of exclusive B-->K KsK-pi+ decays collected with the Belle detector at the KEKB asymmetric energy e+e- collider. The measured mass of the peak is M=3654+-6(stat)+-8(syst) MeV/c^2 and we place a 90% confidence level upper limit on the width of Gamma<55 MeV/c^2. The properties agree with heavy-quark potential model expectations for the eta_c(2S), the n=2 singlet S charmonium state.

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S. -K. Choi. 2002-05-31. Observation of the eta_c(2S) in exclusive B-->K KsK-pi+ decays. https://doi.org/10.1103/physrevlett.89.102001

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