Global effective-field-theory analysis of new-physics effects in (semi)leptonic kaon decays

We analyze the decays K -> pi l nu and P -> l nu (P = K, pi, l = e, mu) using a low-energy Effective-Field-Theory approach to parametrize New Physics and study the complementarity with baryon beta decays. We then provide a road map for a global analysis of the experimental data, with all the Wilson coefficients simultaneously, and perform a fit leading to numerical bounds for them and for V-us. A prominent result of our analysis is a reinterpretation of the well-known V-ud-V-us diagram as a strong constraint on new physics. Finally, we reinterpret our bounds in terms of the SU(2)(L) x U(1)Y-invariant operators, provide bounds to the corresponding Wilson coefficients at the TeV scale and compare our results with collider searches at the LHC.