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arXiv · 2007.05001

Lepton universality and lepton flavor conservation tests with dineutrino modes

Rigo Bause·Hector Gisbert·Marcel Golz·Gudrun Hiller
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Abstract

$SU(2)_L$-invariance links charged dilepton and dineutrino couplings. Phenomenological implications are worked out for flavor changing neutral currents involving strange, charm, beauty and top quark transitions in a model-independent way. We put forward novel tests of lepton universality and lepton flavor conservation in $|\Delta c|= |\Delta u|=1$ and $|\Delta b|= |\Delta q|=1$, $q=d,s$, transitions suitable for the experiments Belle II and BES III. Single top production plus dileptons uniquely probes semileptonic four-fermion $|\Delta t|= |\Delta q'|=1$, $q'=u,c$, couplings and further study at the LHC is encouraged. Tests with single top production associated with dileptons and missing energy are suitable for study at future $e^+ e^-$ or muon colliders.

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Rigo Bause, Hector Gisbert, Marcel Golz, Gudrun Hiller. 2020-07-09. Lepton universality and lepton flavor conservation tests with dineutrino modes. https://arxiv.org/abs/2007.05001

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