Exploring SMEFT operators through single top-quark production associated with the Higgs boson at the LHC

TL;DR

This paper investigates how SMEFT operators affect single top-quark production with a Higgs boson at the LHC, developing a method to constrain these operators and exploring the potential for discovering new physics signatures.

Contribution

It introduces a strategy to constrain SMEFT Wilson coefficients using LHC data for tHq production, offering a complementary approach to global fits and analyzing discovery prospects.

Findings

Best-fit values of SMEFT Wilson coefficients obtained.

Potential for discovering SMEFT effects in tHq at 13 TeV LHC.

Significant excess signals could be observed with high luminosity.

Abstract

The Standard Model effective field theory (SMEFT) provides a general framework to include the dynamics of the beyond standard model physics residing at a certain higher energy scale $\Lambda$. We study the top-quark production along with a Higgs boson and a jet (tHq) at the LHC experiment within the framework of the SMEFT. First, identifying the relevant sensitive dimension-6 SMEFT operators, a strategy is developed to constrain the Wilson Coefficients (WC) corresponding to these associated SMEFT operators using the latest LHC measurements, providing a complementary way to the global-fit approach. The best-fit values of these WCs are presented. Finally, we discuss the discovery potential of the signatures of those operators. We find that a discoverable excess due to SMEFT effects can be observed in the tHq process at the LHC with the center of mass energy $\sqrt{s}=13$ TeV and integrated luminosity options ${\cal L}=$300 $\rm fb^{-1}$ and 3000 $\rm fb^{-1}$.