Associated production of Higgs and single top at the LHC in presence of the SMEFT operators

TL;DR

This paper investigates how dimension-six SMEFT operators affect single top and Higgs production at the LHC, revealing potential deviations from the Standard Model and setting bounds on new physics parameters.

Contribution

It introduces a detailed analysis of SMEFT operators' impact on top-Higgs production, employing machine learning to improve sensitivity and derive bounds from current and future LHC data.

Findings

Effective operators can significantly modify top-Higgs Yukawa coupling bounds.

Machine learning techniques enhance the sensitivity to new physics signals.

Current data constrains the coefficients of relevant four-fermion operators.

Abstract

We analyse the single top production in association with the Higgs at the Large Hadron Collider (LHC) using Standard Model (SM) effective operators upto dimension six. We show that the presence of effective operators can significantly alter the existing bound on the top-Higgs Yukawa coupling. We analyse events at the LHC with 35.9 and 137(140) fb$^{-1}$ integrated luminosities using both cut-based and machine learning techniques to probe new physics (NP) scale and operator coefficients addressing relevant SM background reduction. The four fermi effective operator(s) that contributes to the signal, turns out to be crucial and a bound on the operator coefficient is obtained from the present data and for future sensitivities.