Single Top Production at Next-to-Leading Order in the Standard Model Effective Field Theory

TL;DR

This paper calculates next-to-leading order QCD corrections for single top production in the Standard Model, including dimension-six operators, enhancing theoretical precision for experimental analysis and interpretation.

Contribution

It provides the first NLO QCD calculations for single top production with dimension-six operators, enabling more accurate experimental constraints.

Findings

QCD corrections significantly affect operator limits

Distributions of key observables are modified nontrivially

Calculation can be matched to parton shower programs

Abstract

Single top production processes at hadron colliders provide information on the relation between the top quark and the electroweak sector of the standard model. We compute the next-to-leading order QCD corrections to the three main production channels: $t$-channel, $s$-channel and $tW$ associated production, in the standard model including operators up to dimension-six. The calculation can be matched to parton shower programs and can therefore be directly used in experimental analyses. The QCD corrections are found to significantly impact the extraction of the current limits on the operators, because both of an improved accuracy and a better precision of the theoretical predictions. In addition, the distributions of some of the key discriminating observables are modified in a nontrivial way, which could change the interpretation of measurements in terms of UV complete models.