High-precision determination of the Ke3 radiative corrections

Abstract

We report a high-precision calculation of the Standard Model electroweak radiative corrections in the K→πe+ν(γ) decay as a part of the combined theory effort to understand the existing anomaly in the determinations of Vus. Our new analysis features a chiral resummation of the large infrared-singular terms in the radiative corrections and a well-under-control strong interaction uncertainty based on the most recent lattice QCD inputs. While being consistent with the current state-of-the-art results obtained from chiral perturbation theory, we reduce the existing theory uncertainty from 10−3 to 10−4. Our result suggests that the Standard Model electroweak effects cannot account for the Vus anomaly.