Matching in $$pp\to t\overline{t}W/Z/h+$$ jet SMEFT studies
A bstract In this paper, we explore the impact of extra radiation on predictions of $$pp\to \mathrm{t}\overline{\mathrm{t}}\mathrm{X},\mathrm{X}=\mathrm{h}/{\mathrm{W}}^{\pm }/\mathrm{Z}$$ pp → t t ¯ X , X = h / W ± / Z processes within the dimension-6 SMEFT framework. While full next-to-leading order calculations are of course preferred, they are not always practical, and so it is useful to be able to capture the impacts of extra radiation using leading-order matrix elements matched to the parton shower and merged. While a matched/merged leading-order calculation for $$\mathrm{t}\overline{\mathrm{t}}\mathrm{X}$$ t t ¯ X is not expected to reproduce the next-to-leading order inclusive cross section precisely, we show that it does capture the relative impact of the EFT effects by considering the ratio of matched SMEFT inclusive cross sections to Standard Model values, $${\sigma}_{\mathrm{SM}\mathrm{EFT}}\left(\mathrm{t}\overline{\mathrm{t}}\mathrm{X}+\mathrm{j}\right)/{\sigma}_{\mathrm{SM}}\left(\mathrm{t}\overline{\mathrm{t}}\mathrm{X}+\mathrm{j}\right)\equiv \mu$$ σ SMEFT t t ¯ X + j / σ SM t t ¯ X + j ≡ μ . Furthermore, we compare leading order calculations with and without extra radiation and find several cases, such as the effect of the operator $$\left({\varphi}^{\dagger }i{\overleftrightarrow{D}}_{\mu}\varphi \right)\left(\overline{t}{\gamma}^{\mu }t\right)$$ φ † i D ↔ μ φ t ¯ γ μ t on $$\mathrm{t}\overline{\mathrm{t}}\mathrm{h} more » Authors: ; ; ; ; ; Award ID(s): Publication Date: NSF-PAR ID: 10292616 Journal Name: Journal of High Energy Physics Volume: 2021 Issue: 6 ISSN: 1029-8479 Sponsoring Org: National Science Foundation ##### More Like this 1. Abstract The rate for Higgs ($${\mathrm{H}} $$H ) bosons production in association with either one ($${\mathrm{t}} {\mathrm{H}} $$t H ) or two ($${\mathrm{t}} {{\overline{{{\mathrm{t}}}}}} {\mathrm{H}} $$t t ¯ H ) top quarks is measured in final states containing multiple electrons, muons, or tau leptons decaying to hadrons and a neutrino, using proton–proton collisions recorded at a center-of-mass energy of$$13\,\text {TeV} $$13 TeV by the CMS experiment. The analyzed data correspond to an integrated luminosity of 137$$\,\text {fb}^{-1}$$fb - 1 . The analysis is aimed at events that contain$${\mathrm{H}} \rightarrowmore »
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