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arXiv · hep-ph/9307295

Universality-Breaking Effects in Leptonic Z Decays

J. Bernabeu·J. Korner·A. Pilaftsis·K. Schilcher
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Abstract

We analyze the possibility of universality violation in diagonal leptonic decays of the $Z$ boson, in the context of interfamily "see-saw" models. In a minimal extension of the Standard Model with right-handed neutrino fields, we find that universality-breaking effects increase quadratically with the heavy Majorana neutrino mass and may be observed in the running $LEP$ experiments.

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J. Bernabeu, J. Korner, A. Pilaftsis, K. Schilcher. 1993-07-19. Universality-Breaking Effects in Leptonic Z Decays. https://doi.org/10.1103/physrevlett.71.2695

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