Threshold corrections in SMEFT

TL;DR

This work provides analytic one-loop threshold corrections for dimension-six SMEFT in two electroweak input schemes, establishing a universal link between broken-phase experimental inputs and MSbar symmetric-phase parameters used for SMEFT RG analyses and UV-model matching. It also derives the full one-loop running of the strong coupling in SMEFT, including electroweak effects and decoupling constants when heavy states are integrated out, and it demonstrates that loop-level corrections can be enhanced by tadpoles and top-quark effects, potentially shifting key parameters by several percent. The results are cross-checked for gauge invariance and consistency with SM limits, and they are presented in a form ready for direct integration into public RG-running and matching codes, enabling more precise SMEFT phenomenology in both bottom-up and top-down analyses.

Abstract

Threshold corrections provide a universal link between experimentally measured broken-phase parameters and $\overline{\hbox{MS}}$ renormalised symmetric-phase parameters used in SMEFT renormalisation-group (RG) analyses and matching to new-physics models. In this work we compute in analytic form the complete set of one-loop threshold corrections in dimension-six SMEFT, using two electroweak input schemes and including tadpole effects in the Fleischer-Jegerlehner (FJ) scheme. As a by-product of the analysis, we obtain the full one-loop running of the strong coupling in SMEFT, including electroweak corrections, and the associated decoupling constants when the top quark and heavy electroweak bosons are integrated out. Although generally moderate, the loop-level dimension-six corrections can be enhanced through tadpole effects and top-quark loops, and can shift symmetric phase parameters at the 5% level under reasonable assumptions. Our results constitute a process-independent ingredient which can be readily implemented in public RG-running and matching codes in SMEFT.