Effective operators in $t$-channel single top production and decay

TL;DR

This paper investigates how dimension-6 effective operators affect single top quark production and decay in the t-channel at the LHC, providing insights into potential new physics signals and CP violation effects.

Contribution

It performs NLO QCD calculations including effective operators, analyzing their impact on kinematic distributions to aid in setting bounds on new physics parameters.

Findings

Sensitivity to effective operators varies with kinematic distributions

Potential to constrain CP-violating operators

Results assist in developing strategies for new physics searches

Abstract

The production of a single top quark in the $t$-channel and its subsequent decay is studied at NLO accuracy in QCD, augmented with the relevant dimension-6 effective operators from the Standard Model Effective Theory. We examine various kinematic and angular distributions for proton-proton collisions at the LHC at 13 TeV, in order to assess the sensitivity to these operators, both with and without the top quark narrow width approximation. Our results will be helpful when devising strategies to establish bounds on their coefficients, including the amount of CP violation of the weak dipole operator.