A New Theory Framework for the Electroweak Radiative Corrections in K_l3 Decays

Daniel Galviz (HISKP)

We propose a new theory framework to study the electroweak radiative corrections in K_l3 decays by combining the classic current algebra approach with the modern effective field theory.  Under this framework, the most important O(G_Fα) radiative corrections are described by a single tensor T^μν involving the time-ordered product between the charged weak current and the electromagnetic current, and all remaining pieces are calculable order-by-order in Chiral Perturbation Theory.  This finding may serve as a basis for a more precise extraction of the matrix element V_us in the future.

HISKP, Seminarraum II