aMC@NLO predictions for Wjj production at the Tevatron
Rikkert Frederix, Stefano Frixione, Valentin Hirschi, Fabio Maltoni, Roberto Pittau, Paolo Torrielli
TL;DR
This work delivers the first fully automated NLO QCD prediction for $p\bar{p}\to \ell\nu jj$ events matched to a parton shower via MC@NLO, focusing on the Tevatron. It demonstrates that generation cuts can be chosen without bias and that the perturbative expansion is well-behaved across observables relevant to W+jets analyses. The authors find moderate NLO corrections and argue that, within the studied framework, these corrections cannot account for the CDF dijet-mass excess. The results provide robust, experimentally usable predictions to test the SM background in $Wjj$ measurements and constrain potential BSM interpretations.
Abstract
We use aMC@NLO to predict the lv+ 2-jet cross section at the NLO accuracy in QCD matched to parton shower simulations. We find that the perturbative expansion is well behaved for all the observables we study, and in particular for those relevant to the experimental analyses. We therefore conclude that NLO corrections to this process cannot be responsible for the excess of events in the dijet invariant mass observed by the CDF collaboration.