Anomalous coupling, top-mass and parton-shower effects in W + W − production

We calculate the process pp→W⁺W⁻ →e⁺ νₑμ⁻ ν ¯μ at NLO QCD, including also effective field theory (EFT) operators mediating the ggW⁺ W⁻ interaction, which first occur at dimension eight. We further combine the NLO and EFT matrix elements produced by GoSam with the Herwig7/Matchbox framework, which offers the possibility to study the impact of a parton shower. We assess the effects of the anomalous couplings by comparing them to top-mass effects as well as uncertainties related to variations of the renormalisation, factorisation and hard shower scales.