Sterile neutrinos and RK
نویسنده
چکیده
We consider an enhancement in the violation of lepton flavour universality in light meson decays arising from modified Wlν couplings in the standard model minimally extended by sterile neutrinos. Due to the presence of additional mixings between the active neutrinos and the new sterile states, the deviation from unitarity of the leptonic mixing matrix intervening in charged currents might lead to a tree-level enhancement of RP = Γ(P → eν)/Γ(P → μν), with P = K,π. These enhancements are illustrated in the case of the inverse seesaw, showing that one can saturate the current experimental bounds on ∆rK (and ∆rπ), while in agreement with the different experimental and observational constraints.
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