| Although the Standard Model(SM) has been tested by many precision experimental tests,many problems remain unsolved,such as the dynamics responsible for the electroweak symmetry breaking(EWSB),the problem of neutrino mass,the origin of Parity violation and CP violation.Thus,searching for new physics beyond the SM is the main research topic on particle physics and is also the major object of future high energy experiments.Among new physics proposed from various point of view,many models predict heavy gauge bosons outside of the Standard Model(SM),generically denoted by W′±and Z′.In most cases W′±and Z′are gauge bosons of a spontaneously broken S U(2) gauge theory.Different models give specific symmetry breaking mechanisms and there exists different couplings between these heavy gauge bosons and the ordinary fermions in the SM.In order to explore various situations as general as possible,it is worthwhile studying the phenomenology of W′±and Z′in a model independent way.Since the S U(2)L(?)U(1)Y gauge theory in the SM has been confirmed experimentally, the minimal extension which can accommodate W′±and Z′is the group S U(2)1(?)S U(2)2(?)U(1).We are interested in the situation in which except discovered particles in SM,the lowest new particles which are expected to show up in upcoming collider experiments are W′±,Z′and a light neutral Higgs which is introduced here mainly to keep the theory unitary at TeV energy region.We have constructed a complete list of electroweak chiral Lagrangian for W′±,Z′and a neutral light Higgs with symmetry S U(2)1(?)S U(2)2(?)U(1).The bosonic part is accurate up to order of p4.The matter part involving various fermion representation arrangements includes dimension three Yukawa type and dimension four gauge type operators.This Lagrangian may be a general platform to investigate various interactions phenomenologically.Some constraints on the coefficients of the Lagrangian are given from low energy phenomenology,especially from K0-(?)0,Bd0-(?)d0 and Bs0-(?)s0 mass differences and indirect CP violation parameter∈K for K mesons.It is shown that there exists proper parameter space to loosen constrain on the mass of W′.These constrains also give some clues for future new model building.
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