Abstract
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 $e\nu \mu^+\mu^-$ 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.
Highlights
The properties of the Standard Model (SM) have been experimentally verified at the LHC at the O (10–20%) level in the Higgs sector [1] and there is no evidence for the existence of any new particles or interactions at the TeV scale yet
We investigate the role of anomalous gauge boson and fermion couplings in the production of WZ and WþW− pairs at the LHC to next-to-leading-order (NLO) QCD in the Standard Model effective field theory (SMEFT), including dimension-six operators
We combine our WZ results in the leptonic final state eνμþμ− with previous WþW− 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
Summary
The properties of the Standard Model (SM) have been experimentally verified at the LHC at the O (10–20%) level in the Higgs sector [1] and there is no evidence for the existence of any new particles or interactions at the TeV scale yet. WþW− pair production is under good theoretical control in the SM: NNLO QCD [13,14,15] and NLO electroweak [8,9,16] corrections are understood and change the distributions and rates significantly. The leptonic decay channel of WþW− pair production has been studied at NLO in the SMEFT in a previous work [19] We extend those results to include the leptonic decays from WZ pair production at the LHC in the presence of anomalous three-gauge-boson and anomalous fermiongauge-boson couplings. Limits on SMEFT coefficients have been obtained in global fits that include gauge boson pair production, Higgs measurements, electroweak precision measurements, and top-quark measurements [26,27,28,29,30]. We provide fits using WþW− data only in Appendix A, while a discussion about the truncation at order Oð1=Λ2Þ is provided in Appendix B
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
