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QCD Corrections in SMEFT Fits to $WZ$ and $WW$ Production

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 نشر من قبل Samuel Homiller
 تاريخ النشر 2019
  مجال البحث
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We investigate the role of anomalous gauge boson and fermion couplings on the production of $WZ$ and $W^+W^-$ pairs at the LHC to NLO QCD in the Standard Model effective field theory, including dimension-6 operators. Our results are implemented in a publicly available version of the POWHEG-BOX. We combine our $WZ$ results in the leptonic final state $e u mu^+mu^-$ with previous $W^+W^-$ results to demonstrate the numerical effects of NLO QCD corrections on the limits on effective couplings derived from ATLAS and CMS 8 and 13 TeV differential measurements. Our study demonstrates the importance of including NLO QCD SMEFT corrections in the $WZ$ analysis, while the effects on $WW$ production are smaller. We also show that the $mathcal{O}(1/Lambda^4)$ contributions dominate the analysis, where $Lambda$ is the high energy scale associated with the SMEFT.

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