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Excited tau lepton contribution to $W->tau nu(tau)$ decay at the one-loop level

Rodolfo A. Diaz·R. Martinez·O. A. Sampayo
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Abstract

We evaluate the compositeness effects of tau lepton on the vertex W-tau-nu(tau) in the context of an effective Lagrangian approach. We consider that only the third family is composed and we get the corrections to the non universal lepton coupling g_(tau)/g_(e). As the experimental bounds on non universal lepton couplings in W decays are weak, we find that the excited particles contributions do not give realistic limits on the excited mass, since they lead to Lambda<m*.

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Rodolfo A. Diaz, R. Martinez, O. A. Sampayo. 2003-02-07. Excited tau lepton contribution to $W->tau nu(tau)$ decay at the one-loop level. https://doi.org/10.1142/s0217732302008952

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