| This thesis contains two parts, the data quality checks and the physics analyses. The development and upgrade of Data Quality Monitoring (DQM) system, and the studying of tracking efficiency and particle ID efficiency with their corresponding systematic uncertainties are the main works for data quality checks. The weak decay research through J/ψ'Ds-ρ++c.c.and J/ψ'D0K*0+c.c. and excited baryons research through J/ψ(ψ(3686)'pnπ-+c.c. contribute to the physics analyses.The DQM system is used to monitor detector status and data quality in real time during the data taking period. The software development and upgrade for the whole system are introduced in this thesis, including the structure, framework, data-flow, as well as the performance and advantage of the system.The systematic errors of tracking and particle ID are studied using the control sam-ple of J/ψ'ppπ+π-. The tracking and particle ID efficiencies and their correspond-ing systematic errors of proton and pion in both one-dimension and two-dimension are presented. Different influence factors to the efficiencies are also discussed, along with the definition, method guarantees, etc.A search for the rare decays of J/ψ'Ds-ρ++c.c.and J/ψ'D0K*0+c.c. is performed with a data sample of 225.3M J/ψ events collected with the BESⅢ detector, including the selection criteria, background, and systematic errors studies. No evident signal is observed. Using bayesian method, the upper limits on the branching fractions are determined at the 90% confidence level.Based on 225M J/ψ events and 106M ψ(3686) events collected with the BESⅢ detector, J/ψ(ψ(3686)'pnπ-+c.c. are studied, including the event criteria and systematic errors study. The branching fractions are given finally and the "12% rules" have been proved. The branching ratios consist with BESⅡ, and the background levels, statistic and systematic errors are much lower the BESⅡ. Possible N* resonances are observed in pπ and nπ invariant mass, and a partial wave analysis will be needed. |
PDF Full Text Request