Study Of ψ’→Λ(?)ω

The study of baryon spectroscopy is an important part of hadron physics,which provide much important information on the study of hadron’s inner_structure and qCD interaction.Currently,however,we have meagre acknowledge of hadron structure,and large uncertainty of the quality、width and the measurement of branching ratio in baron excited state.Some states which have already confirmed in experiment but different from the prophecy of the theory model.Many baron excited states which are theoretically predicted are still not found.The experiment data of baryon excited state which contained strange quark—hyperon excited state,e.g.Λ*,∑*and(?)*still insufficiency.The BESⅢ collected j/ψ、ψ’ is the ideal place to find and search baryon excited state.In ψ’ decays,the threshold is higher than j/ψ and can produce more heavier hyperon excited state.So this essay do research of ψ’→Λ(?)ω based on the 4.48×108ψ’ event which is collected in 2009 and 2012 by besiii.The branching ratio has been presented,the result including statistic error and systematic error as below:B(ψ’→Λ(?)ω)=(4.82 ± 0.45(stat.)±0.53(syst.))× 10-5 This branching ratio is first observed and measured in the world,and the signal is very clear.Through this measurement,a deep research of resonance Λ*has been made.There is no significance structure of a*,thus the upper limit of branching ratio in 90%confidence level by bayesian method has been made.The result is:B(ψ’→Λ(?)*)or B(ψ’→(?)Λ*)<1.54×10-5...