Bâ†'K^*η^′ Decays And NLO Corrections In The PQCD Approach

B meson decays are important places to test the standard model and search for possible new physics beyond the SM for their special qualities.Recently,theoretical researches for B mesons are being supported strongly by experimental results.The two B factories have collected about 1300 million events of B-(?)pair production,besides,in the forthcoming LHC-b experiments,about 10¹²B_u,d,B_s and B_c events will be produced.However,there exits many errors to calculate the hadronic matrix elements because of the complex of nonperturbative part in B meson decays.Pertrubative QCD(pQCD)is one of main models to calculate the hadronic matrix elements,where the author introduces the transverse momentunκ_ÃŽÂ¥and get the Sudakov form factor to smear the end-point divergence. In this paper,we study the branching ratios and CP violating asymmetries of B→K^*η(′) decays in next-to-leading order(NLO)pQCD.In the second chapter,we firstly give a review of low energy effective Hamiltonian and then several approaches for dealing with hadronic matrix elements,especially the pQCD approach.In the third chapter,we evaluate the branching ratios and the CP violating asymmetries of the four B→K^*η(′)decays in pQCD.We firstly give the theoretical results in leading order pQCD,then we study the theoretical predictions in next to leading order pQCD including vertex corrections,quark-loops and magnetic correction.After our calculations ,we find that the next to leading order contributions have l(?)rge effects on the leading order results.As a result,the branching ratios are consistent with the data considering the uncertainties in experiments and theories but less than the predictions in QCDF.The next to leading order CP violating asymmetries,however,also have large errors compared with the experimental results.In the last chapter,a summary of this paper and some discussions are given.We expect the further progress in both experiments and theories.