First observation of psi(2S)-->K_S K_L
High Energy Physics - Experiment
2019-08-14 v1
Abstract
The decay psi(2S)-->K_S K_L is observed for the first time using psi(2S) data collected with the Beijing Spectrometer (BESII) at the Beijing Electron Positron Collider (BEPC); the branching ratio is determined to be B(psi(2S)-->K_S K_L) = (5.24\pm 0.47 \pm 0.48)\times 10^{-5}. Compared with J/psi-->K_S K_L, the psi(2S) branching ratio is enhanced relative to the prediction of the perturbative QCD ``12%'' rule. The result, together with the branching ratios of psi(2S) decays to other pseudoscalar meson pairs (\pi^+\pi^- and K^+K^-), is used to investigate the relative phase between the three-gluon and the one-photon annihilation amplitudes of psi(2S) decays.
Cite
@article{arxiv.hep-ex/0310024,
title = {First observation of psi(2S)-->K_S K_L},
author = {J. Z. Bai},
journal= {arXiv preprint arXiv:hep-ex/0310024},
year = {2019}
}
Comments
5 pages, 4 figures, 2 tables, submitted to Phys. Rev. Lett