Related papers: Recent BES results and the BESIII upgrade
The lowest lying charmonium system $\eta_c$ has been observed for more than four decades. Studies of its production and decay properties provide an unique platform to investigate the inner structure of charmonium systems, hence improve our…
A high precision measurement of the branching fraction of the decay $J/\psi \to p \bar{p} \eta$ is performed using $(10 087 \pm 44) \times 10^6$ $J/\psi$ events recorded by the {BESIII} detector at the {BEPCII} storage ring. The branching…
Using an $e^+e^-$ collision data sample of $(27.08 \pm 0.14) \times 10^{8}$ $\psi(3686)$ events collected by the BESIII detector, we report the first observation of $\chi_{cJ} \to \Omega^- \bar{\Omega}^+$ ($J=0,\,1,\,2$) decays with…
We report partial wave analysis results for $J/\psi \to \gamma K^+ K^-$ based on $7.8 \times 10^6$ BESI $J/\psi$ events, and find $0^{++}$ to be dominant in the $f_J(1710)$ mass region. Some very preliminary results are presented from the…
By analyzing $(448.1\pm2.9)\times10^6$ $\psi(3686)$ events collected with the BESIII detector operating at the BEPCII collider, the decays of $\chi_{cJ} \to \Lambda\bar \Lambda \eta$ ($J=0$, 1 and 2) are observed for the first time with…
Using a data sample of $(1310.6 \pm 7.0)\times 10^6$ $J/\psi$ events collected with the BESIII detector operating at the BEPCII collider, we perform the first experimental search for invisible decays of a light vector meson…
Using a sample of about 10 billion $J/\psi$ events with the BESIII detector, we search for the weak decays of $J/\psi \to \bar{D}^0\pi^0 + c.c.$, $J/\psi \to \bar{D}^0\eta + c.c.$, $J/\psi \to \bar{D}^0\rho^0 + c.c.$, $J/\psi \to D^-\pi^+ +…
Using a sample of $(2712.4 \pm 14.3)\times 10^6 ~\psi$(3686) events collected by the BESIII detector at the BEPCII collider, we measure the branching fractions of the decays $\chi_{cJ}\to \phi\phi\eta,~\phi\phi\eta^{\prime}$, and~$\phi…
Using a data sample of $4.481\times 10^8 \psi^\prime$ events collected with the BESIII detector, we report the first observation of the four-lepton-decays $J/\psi\to e^+e^-e^+e^-$ and $J/\psi\to e^+e^-\mu^+\mu^-$ utilizing the process…
Based on the data sample of $448.1\times10^{6}$ $\psi(3686)$ events collected with the BESIII detector at BEPCII, we present a study of the decays $\psi(3686)\rightarrow\gamma\chi_{cJ}\rightarrow\gamma\bar{p}K^{*+}\Lambda+c.c.$ and…
In 2009, the BESIII experiment has collected about 225M $\jpsi$ and 106M $\psip$ samples, both of which are the world largest on-peak charmonium production. Based on these dataset, BESIII has made great effort on the study of the charmonium…
Using 14 million psi(2S) data sample collected with BES at BEPC, psi(2S)-> VT, K_long K_short(also J/psi -> K_long K_short), and chi_cJ -> Baryon anti-Baryon decays are measured and compared with theoretical model predications.
R measurement results in 2--5 GeV region by BESII is reported in this talk. The study on $\sigma$ particle in $J/\psi \to \omega \pi^+ \pi^-$, based on $7.8 \times 10^6$ BESI $J/\psi$ data, is also reported.
Using 58 million $J/\psi$ decays, we have investigated the $p \bar{p}$ invariant mass spectrum in the radiative decay $J/\psi \to \gamma p \bar{p}$ and observe a prominent structure with mass near $2m_p$. Fitting with an S-wave…
Using data samples with an integrated luminosity of 22.42 fb$^{-1}$ collected by the BESIII detector operating at the BEPCII storage ring, we measure the cross sections of the $e^{+}e^{-}\rightarrow\etaJ/\psi$ process at center-of-mass…
Based on 7.8 million J/\psi events collected at BEPC, the events for J/\psi \to p\bar{p}\pi^0 and p\bar{p}\eta have been selected and reconstructed. Clear peaks are observed around 1480 MeV in p\pi^0 (\bar{p}\pi^0) invariant mass spectrum…
Using a sample of $2.25\times 10^8$ $J/\psi$ events collected with the BESIII detector at the BEPCII collider, we search for the $J/\psi$ semi-leptonic weak decay $J/\psi \to D^{-}_{s} e^{+}\nu_{e}+c.c.$ with a much higher sensitivity than…
Based on $(106.41 \pm 0.86)\times 10^{6}$ $\psi(3686)$ events collected with the BESIII detector at the BEPCII collider, the branching fractions of $\psi(3686) \to \pi^+\pi^- J/\psi$, $J/\psi \to e^+e^- $, and $J/\psi \to \mu^+\mu^-$ are…
The hadronic decay $\eta_c(2S) \to 3(\pi^+\pi^-)$ is observed with a statistical significance of 9.3 standard deviations using $(448.1\pm2.9)\times10^6$ $\psi(3686)$ events collected by the BESIII detector at the BEPCII collider. The…
Using a sample of $(225.2\pm 2.8)\times 10^6$ $J/\psi$ events collected with the Beijing Spectrometer (BESIII) at the Beijing Electron-Positron Collider, CP and $P$ violating decays of $\eta$, $\eta'$ and $\etac$ into $\pi^+\pi^-$ and…