The bound on the mass of the new gauge boson Z′ from the process μ→3e

The new gauge boson Z′ predicted by the strong top dynamical symmetry breaking models has significant contributions to the lepton flavor changing process μ→3e. We consider the bound on the mass of the new gauge boson Z′ from the experimental value of the branching ratio Br(μ→3e) in the framework of topcolor assisted technicolor models. We find that the precision experimental value of Br(μ→3e) gives a severe bound on the Z′ mass MZ′. For k1⩽1, MZ′ must be larger than 1.64 TeV.