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$τ$ Anomalous Couplings and Radiation Zeros in the $e^+e^- \to τ\barτγ$ process

I. Rodriguez·O. A. Sampayo
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Abstract

The process $e^+e^- \to τ\barτγ$ contains configurations of the four-momenta for which the scattering amplitude vanishes (Radiation Zeros or Null Zone). These Radiation Zeros only occur for couplings given by a gauge theory, in particular the standard model. Therefore they are sensitive to physics beyond the standard model as the anomalous magnetic and weak moment of the $τ$ lepton. In this article we compute the effect of these anomalous interactions on the Radiation Zeros in the above mentioned process.

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I. Rodriguez, O. A. Sampayo. 2003-12-22. $τ$ Anomalous Couplings and Radiation Zeros in the $e^+e^- \to τ\barτγ$ process. https://arxiv.org/abs/hep-ph/0312316

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