Recent BES results and the BESIII upgrade
msra(2007)
摘要
Using 58 million $J/\psi$ and 14 million $\psi(2S)$ events collected by the
BESII detector at the BEPC, branching fractions or upper limits for the decays
$J/\psi$ and $\psi(2S) \to \Lambda \bar{\Lambda} \pi^0$ and $\Lambda
\bar{\Lambda} \eta$ are measured, and the decays of $J/\psi$ and $\psi(2S)$ to
$n K^0_S \bar{\Lambda}+c.c.$ are observed and measured for the first time.
Finally, $R$ 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, $\psi(3770)$, $\psi(4040)$, $\psi(4160)$,
and $\psi(4415)$.
The Beijing Electron Collider is being upgraded to a two-ring collider
(BEPCII) with a design luminosity of $1 \times 10^{33}$cm$^{-2}$ s$^{-1}$ 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 $J/\psi$ events in one year of running. BEPCII and BESIII are
currently nearing completion, and commissioning of both is expected to begin in
mid-2008.
更多查看译文
关键词
high energy physics,center of mass
AI 理解论文
溯源树
样例
![](https://originalfileserver.aminer.cn/sys/aminer/pubs/mrt_preview.jpeg)
生成溯源树,研究论文发展脉络
Chat Paper
正在生成论文摘要