Some results on lepton flavour universality violation

Abstract

Abstract Motivated by recent experimental measurements on flavour physics, in tension with Standard Model predictions, we perform an updated analysis of new physics violating lepton flavour universality, by using the effective Lagrangian approach and in the $$Z^{'}$$ Z′ and $$S_3$$ S3 leptoquark models. We explicitly analyze the impact of considering complex Wilson coefficients in the analysis of B-anomalies, by performing a global fit of $$R_{K}$$ RK and $$R_{K^{*0}}$$ RK∗0 observables, together with $$\varDelta M_s$$ ΔMs and $$A_{CP}^{\mathrm{mix}}$$ ACPmix . The inclusion of complex couplings provides a slightly improved global fit, and a marginally improved $$\varDelta M_s$$ ΔMs prediction.