Abstract
We introduce an improvement to the FxFx matrix element merging procedure for pp → \( t\overline{t}W \) production at NLO in QCD with one and/or two additional jets. The main modification is an improved treatment of jets that are not logarithmically enhanced in the low transverse-momentum regime. We provide predictions for the inclusive cross section and the \( t\overline{t}W \) differential distributions including parton-shower effects. Taking also the NLO EW corrections into account, this results in the most-accurate predictions for this process to date. We further proceed to include the on-shell LO decays of the \( t\overline{t}W \) including the tree-level spin correlations within the narrow-width approximation, focusing on the multi-lepton signatures studied at the LHC. We find a ∼30% increase over the NLO QCD prediction and large non-flat K-factors to differential distributions.
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Frederix, R., Tsinikos, I. On improving NLO merging for \( \mathrm{t}\overline{\mathrm{t}}\mathrm{W} \) production. J. High Energ. Phys. 2021, 29 (2021). https://doi.org/10.1007/JHEP11(2021)029
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DOI: https://doi.org/10.1007/JHEP11(2021)029
Keywords
- NLO Computations
- QCD Phenomenology