Effect Of ?-? Mixing On B?J/?? Decay

In particle physics,the Standard Model(SM),which consists of the quantum chromody-namics and the electroweak unified theory,successfully describes three fundamental interactions in nature such as electromagnetic,strong and weak interactions.The Higgs particle,predicted by the SM,was first discovered at the Large Hadron Collider(LHC)in 2012,further confirm-ing the correctness of the theory.Although the SM is excellent,some "anomalies",such as the matter-antimatter asymmetry of the universe,the huge difference in mass between the three gen-erations of quarks and fine-tuning,can not be explained until now.All these drive people to expand the SM and establish the fundemental theory in the higher-energy scale,namely New Physics beyond the SM.B-meson physics is an ideal place to search for New Physics,and the study of B-meson decay process is the key to extend the SM.In this thesis,we shall study the decay B?J/??,which is suppressed by OZI rule.In this process,the final-state ? meson can be produced by three-gluon fusion mechanism,photon production mechanism,the final-state rescattering,as well as ?-? mixing mechanism.In these four mechanisms,the ?-? mixing mechanism gives the most contribution.Therefore,this thesis mainly investigates the influence of ?-? mixing on B?J/?? process.In the ?-? mixing,the key is the extraction of the mixing angle ?.The mixing angle ? can be obtained by different methods.In this paper,four extraction schemes will be introduced,namely in the Light-cone Quark Model(LCQM),Hidden Local Symmetries(HLS),Chiral perturbation theory(ChPT)as well as Generalized QCD-like Theory(GQCDT).On this basis,we discuss the effects of obtained mixing angles under different schemes on B?J/?? process.In addition,the branching ratios of the quark-level b?cud,b?ccd,b?uud and b?ccs in the quark level decay channels are count by using the ?-? mixing angles in the HLS.This thesis consists of the following parts.In the second chapter,we describe briefly the Standard Model and the theoretical basis used in the study of B?J/?? decay,and show the different contributions of Feynman Diagram to the B?J/?? decay process.In the third chap-ter,we introduc four schemes for extracting the mixing angle.In the fourth chapter,we discuss the influence of the extracted mixing angle on B?J/?? process under different schemes,and in the fifth chapter,we make a summary and prospect.