Studying New Physics Effects In Pure Leptonic And Semileptonic Decays Of B Hadrons

The Standard Model(SM)of particle physics is renormalized theory that based on gauge group SU(3)C(?)SU(2)L(?)U(1)Y.The SM has been established to be the best theory to de-scribe the strong,magnetic and weak interactions,and its predictions stand almost all the tests of the experiments until now.Though the discovery of the Higgs boson at Large Hadron Collider(LHC)makes the SM more perfect,there are also some questions which could not be explained perfectly within the SM.There is still a degree of deviation between theoretical predictions and the experimental results.These problems provide some space for new physics(NP)that beyond the SM.For the exploration of the NP,on the one hand,the physicists can look for NP signals from the high-energy physics experiments directly;on the other hand,it is indirect to detect NP from the flavor physics processes which contain high brightness precise.Heavy flavor physics,especial B physics,plays an important role in testing SM and finding the sign of NP.The research about the B meson and ?b baryon decay processes becomes one of the very active fields.In this thesis,we study the NP effects of B hadron(B meson and Ab baryon)decay processes in different NP models.The NP models which are discussed in this thesis are R-parity violating supersymmetry model,scalar leptoquark(LQ)model and the family non-universal Z' model.There are mainly three parts in this thesis.The first part contains the first chapter and second chapter,in this part,we briefly introduce the research status of heavy flavor physics and SM.Our work is introduced in second part,which contains third,fourth and fifth chapters.The NP effect of Rs?li+lj-and B?K(*)li+lj-(i?j)in R-parity violating supersymmetry model and scalar leptoquark model are given in third and fourth chapter respectivly.The new bounds on NP coupling parameters are obtained from the latest experimental data and these bounds are stronger than existing ones.We give the theoretical predictions of the other physical quantities.We also predict the NP effects on these quantities that have not been measured by experiment,and we find the NP effect of that quantities are very obvious.The NP effects of the decay process for b?sl+l-in the family non-universal Z' model are shown in fifth chapter.We get the expression of different quantities by the helicity amplitude.and the decay processes of B meson and Ab baryon are mainly discussed in this chapter.NP coupling bounds are gotten from the latest experimental data.Using the upper limit of the coupling parameters which obtained from the experimental data,we predict the NP effects on the other physical quantities.We find that there are obvious NP effects on these quantities.The summary and the future development of B physics are shown in the last part.With the rapid development of the high physics,we are looking forward to these experiments will validate our results and predictions.Our result and theory calculation is a complements for future physics and help us to understand different NP models.