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arXiv · 1512.03071

Rare Z Decays and Neutrino Flavor Universality

Gauthier Durieux·Yuval Grossman·Matthias König·Eric Kuflik·Shamayita Ray
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Abstract

We study rare four-body decays of the Z-boson involving at least one neutrino and one charged lepton. Large destructive interferences make these decays very sensitive to the Z couplings to neutrinos. As the identified charged leptons can determine the neutrino flavors, these decays probe the universality of the Z couplings to neutrinos. The rare four-body processes could be accurately measured at future lepton colliders, leading to percent level precision.

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Gauthier Durieux, Yuval Grossman, Matthias König, Eric Kuflik, Shamayita Ray. 2015-12-09. Rare Z Decays and Neutrino Flavor Universality. https://doi.org/10.1103/physrevd.93.093005

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