Phenomenology of $t\bar{t}j + X$ production at the LHC

TL;DR

This paper provides detailed phenomenological predictions for $t\bar{t}j + X$ production at the LHC, focusing on theoretical uncertainties, input parameter dependence, and top-quark mass extraction methods.

Contribution

It introduces the first application of the MSR top-quark mass scheme to $t\bar{t}j + X$ production and offers reference predictions across multiple mass renormalization schemes.

Findings

Reference predictions for the ${\cal R}$ distribution in different schemes.

Analysis of theoretical uncertainties and parameter dependencies.

Insights into top-quark mass extraction from cross-section measurements.

Abstract

We present phenomenological results for $t\bar{t}j + X$ production at the Large Hadron Collider, of interest for designing forthcoming experimental analyses of this process. We focus on those cases where the $t\bar{t}j + X$ process is considered as a signal. We discuss present theoretical uncertainties and the dependence on relevant input parameters entering the computation. For the ${\cal R}$ distribution, which depends on the invariant mass of the $t\bar{t}j$-system, we present reference predictions in the on-shell, $\overline{\mbox{MS}}$ and MSR top-quark mass renormalization schemes, applying the latter scheme to this process for the first time. Our conclusions are particularly interesting for those analyses aiming at extracting the top-quark mass from cross-section measurements.