Flavor non-universal vector leptoquark imprints in K→πνν¯ and ΔF = 2 transitions

We analyze K→πνν¯ rates in a model with a TeV-scale leptoquark addressing B-meson anomalies, based on the flavor non-universal 4321 gauge group featuring third-generation quark-lepton unification. We show that, together with the tight bounds imposed by ΔF=2 amplitudes, the present measurement of B(K+→π+νν¯) already provides a non-trivial constraint on the model parameter space. In the minimal version of the model, the deviations from the Standard Model in B(K+→π+νν¯) are predicted to be in close correlation with non-standard effects in the Lepton Flavor Universality ratios RD and RD⁎. With the help of future data, these correlations can provide a decisive test of the model.