X. C. Meng
A5031323348- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- High-Energy Particle Collisions Research
- Dark Matter and Cosmic Phenomena
- Adaptive Control of Nonlinear Systems
- Particle Detector Development and Performance
- Nuclear physics research studies
- Distributed Control Multi-Agent Systems
- Neutrino Physics Research
- Atomic and Subatomic Physics Research
- Underwater Vehicles and Communication Systems
- Medical Imaging Techniques and Applications
- Digital Rights Management and Security
- Guidance and Control Systems
- Scientific Research and Discoveries
- Adaptive Dynamic Programming Control
- Smart Grid Security and Resilience
- Radioactive Decay and Measurement Techniques
- Sports Dynamics and Biomechanics
- Superconducting Materials and Applications
- Mechanical and Optical Resonators
- Particle Accelerators and Free-Electron Lasers
- International Science and Diplomacy
- Radiomics and Machine Learning in Medical Imaging
- Quantum chaos and dynamical systems
Shanghai Maritime University
2023-2024
Institute of High Energy Physics
1995-2020
The University of Texas at Dallas
2020
Chinese Academy of Sciences
2015
China Center of Advanced Science and Technology
2004
Guangxi Normal University
2003
Liaoning University
2003
University of Idaho
2000
Massachusetts Institute of Technology
1995
We observe a narrow enhancement near 2m(p) in the invariant mass spectrum of pp pairs from radiative J/psi-->gammapp decays. No similar structure is seen J/psi-->pi(0)pp The results are based on an analysis 58 x 10(6) event sample J/psi decays accumulated with BESII detector at Beijing electron-positron collider. can be fit either S- or P-wave Breit-Wigner resonance function. In case S-wave fit, peak below M=1859(+3)(-10) (stat)+5-25(syst) MeV/c(2) and total width Gamma<30 90% confidence...
We report values of R = sigma(e(+)e(-)-->hadrons)/sigma(e(+)e(-)-->mu(+)mu(-)) for 85 center-of-mass energies between 2 and 5 GeV measured with the upgraded Beijing Spectrometer at Electron-Positron Collider.
Using the upgraded Beijing Spectrometer, we have measured total cross section for e+e− annihilation into hadronic final states at center-of-mass energies of 2.6, 3.2, 3.4, 3.55, 4.6, and 5.0 GeV. Values R, σ(e+e−→hadrons)/σ(e+e−→μ+μ−), are determined.Received 28 July 1999DOI:https://doi.org/10.1103/PhysRevLett.84.594©2000 American Physical Society
This paper is aiming at enabling the underactuated surface vessels (USVs) to complete tracking task with high precision and fast convergence under influence of unknown external interference, dynamic uncertainty, input saturation, limited communication resources, actuator failure. Specifically, a trajectory control scheme designed using virtual switching, robust self-adaptation, finite-time, event-triggered, disturbance compensation techniques. The norm calculation performed on lateral...
Results are presented on ψ(2S) and J/ψ hadronic decays to K0SpK−n̄ K0S¯pK+n final states from data samples of 14 million 58 events accumulated at the BES II detector. No Θ(1540) signal, pentaquark candidate, is observed, upper limits set for B(ψ(2S)→Θ¯Θ→K0SpK−n̄+K0S¯pK+n)<0.84×10−5 B(J/→ψΘ¯Θ→K0SpK−n̄+K0S¯pK+n)<1.1×10−5 90% confidence level. For single production, determined by our analysis also order 10−5 in both decays. Received 4 February...
The deployment of Large Language Models (LLMs) in recommender systems for predicting Click-Through Rates (CTR) necessitates a delicate balance between computational efficiency and predictive accuracy. This paper presents an optimization framework that combines Retrieval-Augmented Generation (RAG) with innovative multi-head early exit architecture to concurrently enhance both aspects. By integrating Graph Convolutional Networks (GCNs) as efficient retrieval mechanisms, we are able...
Decays of the ψ(2S) into vector plus tensor meson final states have been studied with 14 million events collected BESII detector. The branching fractions ψ(2S)→ωf2(1270), ρa2(1320), K*(892)0K2*(1430)0+c.c., and φf2′(1525) are determined. They improve upon previous BESI results confirm violation "12%" rule for decays to VT channels higher precision.Received 4 December 2003DOI:https://doi.org/10.1103/PhysRevD.69.072001©2004 American Physical Society
Results are presented on $J/\ensuremath{\psi}$ radiative decays to ${K}^{+}{K}^{\ensuremath{-}}$ and ${K}_{S}^{0}{K}_{S}^{0}$ based a sample of 58M events taken with the BES II detector. A partial wave analysis is carried out using relativistic covariant tensor amplitude method in 1--2 GeV mass range. There conspicuous production due ${f}_{2}^{\ensuremath{'}}(1525)$ ${f}_{0}(1710).$ The latter peaks at $1740\ifmmode\pm\else\textpm\fi{}{4}_{\ensuremath{-}25}^{+10}\mathrm{MeV}$ width...
Using 58 million J/ψ and 14 ψ(2S) decays obtained by the BES II experiment, branching fraction of J/→ψπ+π−π0 is determined. The result (2.10±0.12)×10−2, which significantly higher than previous measurements.Received 5 February 2004DOI:https://doi.org/10.1103/PhysRevD.70.012005©2004 American Physical Society
Hadronic decays of the P-wave spin-triplet charmonium states χcJ(J=0,1,2) are studied using a sample ψ(2S) collected by BES detector operating at BEPC storage ring. Branching fractions for χc1→K0SK+π−+c.c., χc0→K0SK0S, χc2→K0SK0S, χc0→φφ, χc2→φφ and χcJ→K+K−K+K− measured first time, those χcJ→π+π−π+π−, χcJ→π+π−K+K−, χcJ→π+π−p¯p χcJ→3(π+π−) with improved precision. In addition, we determine masses χc0 ηc to be Mχc0=3414.1±0.6(stat)±0.8(syst)MeV Mηc=2975.8±3.9(stat)±1.2(syst)MeV. Received 15...
The Beijing Spectrometer (BES) experiment has observed purely leptonic decays of the ${D}_{s}$ meson in reaction ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{D}_{s}^{+}{D}_{s}^{\ensuremath{-}}$ at a c.m. energy 4.03 GeV. Three events are which one hadronically to $\ensuremath{\varphi}\ensuremath{\pi}$, ${\overline{K}}^{*0}K$, or ${\overline{K}}^{0}K$, and other leptonically $\ensuremath{\mu}{\ensuremath{\nu}}_{\ensuremath{\mu}}$...
The decay ψ(2S)→KS0KL0 is observed using ψ(2S) data collected with the Beijing Spectrometer at Electron-Positron Collider; branching fraction determined to be B(ψ(2S)→KS0KL0)=(5.24±0.47±0.48)×10−5. Compared J/ψ→KS0KL0, enhanced relative prediction of perturbative QCD "12%" rule. result, together fractions decays other pseudoscalar meson pairs (π+π− and K+K−), used investigate phase between three-gluon one-photon annihilation amplitudes decays.Received 13 October...
Using $\gamma \gamma J/\psi, J/\psi \ra e^+ e^-$ and $\mu^+ \mu^-$ events from a sample of $14.0\times 10^6$ $\psip$ decays collected with the BESII detector, branching fractions for $\psip\ra \pi^0\J$, $\eta\J$, $\psi(2S)\ar\gamma\chi_{c1},\gamma\chi_{c2}\ar\gamma\gamma\jpsi$ are measured to be $B(\psip\ra \pi^0\J) = (1.43\pm0.14\pm0.13)\times 10^{-3}$, \eta\J) (2.98\pm0.09\pm0.23)%$, $B(\psi(2S)\ar\gamma\chi_{c1}\ar\gamma\gamma\jpsi) (2.81\pm0.05\pm 0.23)%$,...
This paper deals with the improvement for tracking performance of underactuated surface vessels (USVs) under input saturation and actuator faults. The neural networks (NNs) are used to reconstruct dynamic uncertainty ship, an adaptive law is designed compensate adverse effects external unknown disturbances bias faults on system. To improve system, a nonlinear link added in design process control scheme adjust system error feedback, finite-time (FTC) technology further steady-state transient...
The processes $\ensuremath{\psi}(2S)\ensuremath{\rightarrow}\ensuremath{\gamma}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$, $\ensuremath{\gamma}{K}^{+}{K}^{\ensuremath{-}}$, and $\ensuremath{\gamma}p\overline{p}$ have been studied using a sample of $3.79\ifmmode\times\else\texttimes\fi{}{10}^{6}\ensuremath{\psi}(2S)$ decays. We determine the total width ${\ensuremath{\chi}}_{c0}$ to be...
The data on $J/\ensuremath{\psi}\ensuremath{\rightarrow}\ensuremath{\gamma}{K}^{+}{K}^{\ensuremath{-}}$ from the BES experiment at Beijing electron-positron collider have been analyzed. We find two resonances in 1.7 GeV region which were identified as ${f}_{J}(1710)$: a scalar with mass $1781\ifmmode\pm\else\textpm\fi{}{8}_{\ensuremath{-}31}^{+10}(\mathrm{MeV})$ and width $85\ifmmode\pm\else\textpm\fi{}{24}_{\ensuremath{-}19}^{+22}(\mathrm{MeV})$, tensor...
The branching ratio of $J/\stackrel{\ensuremath{\rightarrow}}{\ensuremath{\psi}}{K}_{S}^{0}{K}_{L}^{0}$ is measured with improved precision to be $\mathcal{B}(J/\stackrel{\ensuremath{\rightarrow}}{\ensuremath{\psi}}{K}_{S}^{0}{K}_{L}^{0})=(1.82\ifmmode\pm\else\textpm\fi{}0.04\ifmmode\pm\else\textpm\fi{}0.13)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$ using $J/\ensuremath{\psi}$ data collected the Beijing Spectrometer (BESII) at Electron-Positron Collider. This result used test...
This paper studies the trajectory tracking control problem of underactuated unmanned surface vessels (USVs) under influence internal and external uncertainties, actuator faults, injection deception attacks. In design, we separately designed virtual adaptive laws to compensate for time-varying gains suffered by kinematics channel combined event-triggered (ETC) mechanism establish an online approximator channels loss-of-effectiveness (LOE) bias faults system. Combining robust neural damping...