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Study of the P-wave charmonium state χ_{cJ} in ψ(2S) decays

J. Z. Bai
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Abstract

The processes $ψ(2S)\to γπ^+ π^-$, $γK^+ K^-$ and $γp \bar{p}$ have been studied using a sample of $3.7 \times 10^6$ produced $ψ(2S)$ decays. We determine the total width of the $χ_{c0}$ to be $Γ^{tot}_{χ_{c0}} = 14.3\pm 2.0\pm 3.0$ MeV. We present the first measurement of the branching fraction $B(χ_{c0} \to p \bar{p}) = (16.3 \pm 4.4 \pm 5.4)\times 10^{-5}$, where the first error is statistical and the second one systematic. Branching fractions of $χ_{c0,2} \to π^+ π^-$ and $K^+ K^-$ are also reported.

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J. Z. Bai. 1998-10-26. Study of the P-wave charmonium state χ_{cJ} in ψ(2S) decays. https://doi.org/10.1103/physrevlett.81.3091

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