Recent BES results on charmonium decays

TL;DR

This paper reports recent experimental results from BES on charmonium decays, including measurements of decay modes, tests of theoretical models like pQCD and the color-octet mechanism, and searches for CP violation.

Contribution

It provides new experimental data on various charmonium decay channels and tests several theoretical predictions, advancing understanding of QCD in charmonium systems.

Findings

Observation of psi'-->K_S K_L decay.

Measurement of relative phase between strong and electromagnetic decays.

Test of the pQCD 12% rule and the color-octet mechanism.

Abstract

Recent results on charmonia decays at BES/BEPC are reported, including the observation of psi'-->K_S K_L, psi'--> Vector + Tensor for the measurement of the relative phase between the strong and electromagnetic decays of psi' and a test of the pQCD ``12% rule'' between psi' and J/psi decays; the study of psi'--> gamma gamma J/psi for the determination of psi'--> pi^0 J/psi, eta J/psi, gamma chi_c1 and gamma chi_c2 decay branching fractions; the test of the color-octet mechanism via chi_cJ--> p \bar{p} and chi_cJ--> \Lambda \bar{\Lambda}; and a search for the CP violating process psi' and J/psi--> K_S K_S.