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The decays χc1 → J=ψμþμ− and χc2 → J=ψμþμ− are observed and used to study the resonance parameters of the χc1 and χc2 mesons. The masses of these states are measured to be mðχc1Þ¼ 3510.710.04ðstatÞ0.09ðsystÞ MeV and mðχc2Þ¼3556.100.06ðstatÞ0.11ðsystÞ MeV, where the knowledge of the momentum scale for charged particles dominates the systematic uncertainty. The momentum-scale uncertainties largely cancel in the mass difference mðχc2Þ−mðχc1Þ¼ 45.390.07ðstatÞ0.03ðsystÞ MeV. The natural width of the χc2 meson is measured to be Γðχc2Þ¼2.100.20ðstatÞ0.02ðsystÞ MeV. These results are in good agreement with and have comparable precision to the current world averages.