Lepton universality and lepton flavor conservation tests with dineutrino modes

Abstract

Abstract$$SU(2)_L$$ S U ( 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 $$|\varDelta c|= |\varDelta u|=1$$ | Δ c | = | Δ u | = 1 and $$|\varDelta b|= |\varDelta q|=1$$ | Δ b | = | Δ q | = 1 , $$q=d,s$$ q = d , s , transitions suitable for the experiments Belle II and BES III. Single top production plus dileptons uniquely probes semileptonic four-fermion $$|\varDelta t|= |\varDelta q'|=1$$ | Δ t | = | Δ q ′ | = 1 , $$q'=u,c$$ 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 $$e^+ e^-$$ e + e - or muon colliders.