English

Recent BES results and the BESIII upgrade

High Energy Physics - Experiment 2007-12-19 v1

Abstract

Using 58 million J/ψJ/\psi and 14 million ψ(2S)\psi(2S) events collected by the BESII detector at the BEPC, branching fractions or upper limits for the decays J/ψJ/\psi and ψ(2S)ΛΛˉπ0\psi(2S) \to \Lambda \bar{\Lambda} \pi^0 and ΛΛˉη\Lambda \bar{\Lambda} \eta are measured, and the decays of J/ψJ/\psi and ψ(2S)\psi(2S) to nKS0Λˉ+c.c.n K^0_S \bar{\Lambda}+c.c. are observed and measured for the first time. Finally, RR measurement data taken with the BESII detector at center-of-mass energies between 3.7 and 5.0 GeV are fitted to determine resonance parameters of the high mass charmonium states, ψ(3770)\psi(3770), ψ(4040)\psi(4040), ψ(4160)\psi(4160), and ψ(4415)\psi(4415). The Beijing Electron Collider is being upgraded to a two-ring collider (BEPCII) with a design luminosity of 1×10331 \times 10^{33}cm2^{-2} s1^{-1} at 3.89 GeV and will operate between 2 and 4.2 GeV in the center of mass. With this luminosity, the new BESIII detector will beable to collect, for example, 10 billion J/ψJ/\psi events in one year of running. BEPCII and BESIII are currently nearing completion, and commissioning of both is expected to begin in mid-2008.

Keywords

Cite

@article{arxiv.0712.2851,
  title  = {Recent BES results and the BESIII upgrade},
  author = {Frederick A. Harris},
  journal= {arXiv preprint arXiv:0712.2851},
  year   = {2007}
}

Comments

Invited talk at the 11th International Conference on Meson-Nucleon Physics and the Structure of the Nucleon, Sept. 10 - 14, 2007, Julich, Germany, 10 pages

R2 v1 2026-06-21T09:55:05.798Z