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arXiv · hep-ph/0209354

A Measurement of Psi(2S) Resonance Parameters

BES Collaboration·J. Z. Bai
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Abstract

Cross sections for e+e- to hadons, pi+pi- J/Psi, and mu+mu- have been measured in the vicinity of the Psi(2S) resonance using the BESII detector operated at the BEPC. The Psi(2S) total width; partial widths to hadrons, pi+pi- J/Psi, muons; and corresponding branching fractions have been determined to be Gamma(total)= (264+-27) keV; Gamma(hadron)= (258+-26) keV, Gamma(mu)= (2.44+-0.21) keV, and Gamma(pi+pi- J/Psi)= (85+-8.7) keV; and Br(hadron)= (97.79+-0.15)%, Br(pi+pi- J/Psi)= (32+-1.4)%, Br(mu)= (0.93+-0.08)%, respectively.

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BES Collaboration, J. Z. Bai. 2002-12-11. A Measurement of Psi(2S) Resonance Parameters. https://doi.org/10.1016/s0370-2693(02)02909-x

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