High-precision determination of the Ke3 radiative corrections

We report a high-precision calculation of the Standard Model electroweak radiative corrections in the K -> pi e(+)nu(gamma) decay as a part of the combined theory effort to understand the existing anomaly in the determinations of V-us. 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 V-us anomaly. (C) 2021 The Author(s). Published by Elsevier B.V.

Automated summary

This study reports a high-precision calculation of the Standard Model electroweak radiative corrections, revealing an anomaly in the determination of V-us, and suggests that the electroweak effects cannot account for this anomaly.