Related papers: Trigger efficiencies at BES III
In last 10 years, $0^{++}$ resonances have been observed and studied at BES in many processes, such as $J/\psi\to\gamma\pi^+\pi^-\pi^+\pi^-$, $\gamma\pi^+\pi^-$, $\gamma\pi^0\pi^0$, $\gamma K^+K^-$, $\gamma K_SK_S$, $\gamma\omega\phi$,…
The HADES first level trigger is studied for the system p+Ni at a beam energy of 2 AGeV. The timing properties of the trigger signal are reported. The efficiency loss due to deadtime is specified. A trigger requirement of a time overlap…
The studies on the multi-quark candidates, light scalar mesons and excited baryon states at BES are presented, based on $5.8 \times 10^7$ $J/\psi$ data collected with BESII detector. The measurements of some $J/\psi$ and $\eta_c$ decays are…
psi' production is studied in Pb-Pb collisions at 158 GeV/c per nucleon incident momentum. Absolute cross-sections are measured and production rates are investigated as a function of the centrality of the collision. The results are compared…
The coherent photoproduction of $\rm{J/\psi}$ and $\rm{\psi'}$ mesons was measured in ultra-peripheral Pb-Pb collisions at a center-of-mass energy $\sqrt{s_{\mathrm{NN}}}~=~5.02$ TeV with the ALICE detector. Charmonia are detected in the…
In this talk, we present a selection of recent results from BESIII collaboration, including observation of the charmoniumlike states, Zc(3900), Zc(4020) and Zc(4025); observation of e+e- -> gamma X(3872); partial wave analysis of J/psi ->…
In a sample of 58 million $J/\psi$ events collected with the BES II detector, the process J/$\psi\to\gamma\eta_c$ is observed in five decay channels: $\eta_c \to K^+K^-\pi^+\pi^-$, $\pi^+\pi^-\pi^+\pi^-$, $K^\pm K^0_S \pi^\mp$ (with…
The inclusive J/$\psi$ elliptic ($v_2$) and triangular ($v_3$) flow coefficients measured at forward rapidity (2.5 $<y<$ 4) and the $v_2$ measured at midrapidity ($|y|<$ 0.9) in Pb-Pb collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV using the…
The production of J/psi mesons is studied in pp collisions at sqrt(s)=7 TeV with the CMS experiment at the LHC. The measurement is based on a dimuon sample corresponding to an integrated luminosity of 314 inverse nanobarns. The J/psi…
Based on $(4.48 \pm 0.03) \times 10^{8}$ $\psi(3686)$ events collected with the BESIII detector, five $h_c$ hadronic decays are searched for via process $\psi(3686) \to \pi^0 h_c$. Three of them, $h_c \to p \bar{p} \pi^+ \pi^-$, $\pi^+…
This paper will discuss the design and construction of BESIII, which is designed to study physics in the tau-charm energy region utilizing the new high luminosity BEPCII double ring e+e- collider. The expected performance will be given…
We have performed a search for the decays $B^+\to J/\psi p \bar{\Lambda}$ and $B^0\to J/psi p \bar{p}$ in a data set of $(88.9 \pm 1.0)\times 10^6$ $\Upsilon(4S)$ decays collected by the BaBar experiment at the PEP-II $\e^+e^-$ storage ring…
We report the observations of the decays B^+ -> psi(2S) K^+ and B^0 -> psi(2S) K^*(892)^0 in ppbar collisions at a center-of-mass energy of 1.8 TeV using a 110 pb^{-1} data sample recorded by the Collider Detector at Fermilab. We also…
Measurement of the mixing-induced CP-violating phase phi_s in Bs decays is of prime importance in probing new physics. Here 7421 +/- 105 signal events from the dominantly CP-odd final state J/\psi pi+ pi- are selected in 1/fb of pp…
With a sample of 225.3 million $J/\psi$ events taken with the BESIII detector, the decay $J/\psi\rightarrow \gamma 3(\pi^+\pi^-)$ is analyzed. A structure at 1.84 GeV/c$^2$ is observed in the $3(\pi^+\pi^-)$ invariant mass spectrum with a…
The anomalous J/psi suppression in Pb-Pb collisions at 158A GeV observed recently by NA50 can be explained as due to the transition to a new phase of strong J/psi absorption, which sets in when the local energy density exceeds about 3.4…
Based on 14 million psi(2S) and 58 million J/psi events collected by the BESII detector, the leptonic decay of psi(2S) into $\tau^+\tau^-$, psi(2S) multi-body decays, chi_cJ decays, and J/psi hadronic decays are studied, and the branching…
With $1.06\times 10^8$ $\psi(3686)$ events collected with the BESIII detector, the branching fraction of $\psi(3686) \to \omega K^+ K^-$ is measured to be $(1.54 \pm 0.04 \pm 0.11) \times 10^{-4}$. This is the most precise result to date,…
A generic expression of double-parton scattering cross sections in high-energy nucleus-nucleus (A-A) collisions is derived as a function of the corresponding single-parton hard cross sections and of the A-A event centrality. We consider the…
Decays of both $\eta$ and $\eta^\prime$ provide very useful information in our understanding of low-energy QCD, and experimental signatures for these decays would be extremely helpful at BES-III. The rare decays of the $\eta$ and…