Complete NLO corrections to off-shell $\text{t}\overline{\text{t}}\text{Z}$ production at the LHC

TL;DR

This paper provides comprehensive NLO Standard Model predictions for off-shell t-tbar-Z production at the LHC, including all relevant corrections, effects, and decay channels, to support precise experimental measurements.

Contribution

It presents the first complete NLO predictions for off-shell t-tbar-Z production with full matrix elements, resonant and non-resonant contributions, and spin correlations.

Findings

Integrated and differential cross-sections provided

Includes all LO and NLO EW and QCD corrections

Accounts for full off-shell effects and interference

Abstract

Measuring precisely top-pair-associated processes at hadron colliders will become possible with the upcoming LHC running stages. The increased data statistics will especially enable differential measurements leading to an improved characterisation of such processes. Aiming at a consistent data-theory comparison, precise Standard-Model predictions are needed, including higher-order corrections and full off-shell effects. In this work we present NLO-accurate predictions for the production and decay of a top-antitop pair in association with a Z boson at the LHC, in the multi-lepton decay channel. The complete set of LO contributions and NLO corrections of EW and QCD origin is included. The calculation is based on full matrix elements, computed with all resonant and non-resonant contributions, complete spin correlations and interference effects. Integrated and differential cross-sections are presented for a realistic fiducial setup.