The Research Of The CP Violation From The Effect Of Isospin Symmetry Breaking In The PQCD Framework

In the past decades,B physics has been one of the most popular areas in high energy physics.The research of B physics is very important for the accurate test of the standard model and the search for new physics beyond the standard model.At present,the LHCb experiment provides the most important experimental data for B physics research.Isospin symmetry breaking arises from the electroweak interaction and the u-d quark mass difference by the strong interaction,which are known to be tiny.However,we find that isospin symmetry breaking shifts the CP violation due to the new strong phases.In this paper,we study the effect of π0-η-η’ mixing mechanism on direct CP vilation from the process of B→P(V)π0 and Bc→D(s)+π0 in the perturbative QCD factorization approach(P,V refers to pseudoscalar meson and vector meson,respectively).This article first briefly reviews the development of B Physics.Secondly,the perturbative QCD method and π0-η-η’mixing mechanism are introduced in detail.Then,in the framework of perturbative QCD,we investigate the CP breaking for the decay process of B→P(V)π0 and Bc→D(s)+π0 via isospin symmetry breaking effects from the π0-η-η’ mixing mechanism.We find that the isospin symmetry breaking effect via π0-η-η’mixing produces the new strong phase and has a great influence on the CP breaking value.In the decay model (?)→π0η’,the increasing rate of CP violation intermediate value is-65.99%.In addition,isospin symmetry breaking can also change the sign of CP violation of the decay processes (?)→φπ0 and (?)→π0η.At last,summarize and prospect are presented.