Complete study of four top quark production at the LHC in the SMEFT

TL;DR

This paper analyzes four top quark production at the LHC within the SMEFT framework, incorporating all relevant operators and terms, and derives limits on Wilson coefficients using collider data and differential information.

Contribution

It provides a comprehensive tree-level analysis of four top production in SMEFT, including subleading terms and differential data for the first time.

Findings

Subleading terms can significantly impact results.

Limits on SMEFT Wilson coefficients vary with collider setup.

Including differential information improves fit accuracy.

Abstract

We present a study of four top quark production at the LHC in the Standard Model Effective Field Theory (SMEFT). The analysis is performed at the tree-level, including all terms from the mixed QCD-EW-coupling cross-section expansion and all the relevant dimension-six SMEFT operators. We find several cases in which formally subleading terms give rise to significant contributions. Moreover, we obtain limits on the SMEFT Wilson coefficients (WCs), including different collider setups, FCC-hh and HL-LHC, using a simplified chi-square fit. Through the latter, we also assessed the importance of including differential information in the fit.