QCD corrections in Standard Model EFT fits to WZ and WW production

Abstract

We investigate the role of anomalous gauge boson and fermion couplings in the production of WZ and W þ W − pairs at the LHC to next-to-leading-order (NLO) QCD in the Standard Model effective field theory (SMEFT), including dimension-six operators. Our results are implemented in a publicly available version of the POWHEG-BOX. We combine our WZ results in the leptonic final state eνμ þ μ − with previous W þ 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 Oð1=Λ 4 Þ contributions dominate the analysis, where Λ is the high-energy scale associated with the SMEFT.

NLO QCD+NLO EW corrections to diboson production matched to parton shower

“…Tables 1, 2, 3, 4, 5 collect the results at the integrated crosssection level under the event selection of Eqs. (10) and (11) for the processes pp → e + ν e μ − ν μ , pp → μ + ν μ e − e + , and pp → μ + μ − e − e + (dubbed "WW", "WZ", and "ZZ" in the tables). Tables 1 and 2 show the results at LO for fixed and running scales, Tables 3 and 4 contain the results Table 1 Integrated cross sections for the processes pp → e + ν e μ − ν μ , pp → μ + μ − e − e + , and pp → μ + ν μ e − e + at LO under the event selection in Eqs.…”

“…Tables 1 and 2 show the results at LO for fixed and running scales, Tables 3 and 4 contain the results Table 1 Integrated cross sections for the processes pp → e + ν e μ − ν μ , pp → μ + μ − e − e + , and pp → μ + ν μ e − e + at LO under the event selection in Eqs. (10) and (11). The factorization scale is set to μ = Integrated cross sections for the processes pp → e + ν e μ − ν μ , pp → μ + μ − e − e + , and pp → μ + ν μ e − e + at NLO QCD under the event selection in Eqs.…”

“…The factorization scale is set to μ = Integrated cross sections for the processes pp → e + ν e μ − ν μ , pp → μ + μ − e − e + , and pp → μ + ν μ e − e + at NLO QCD under the event selection in Eqs. (10) and (11). The factorization and renormalization scales are set to at NLO QCD for fixed and running scales, while the predictions at NLO EW accuracy (for fixed scales) are presented in Table 5.…”

“…Electroweak boson pair production involving at least a W boson in the final state (W + W − and Z W ± ) is important for collider phenomenology because it is sensitive to the Z W W gauge-boson self interaction, and therefore precision measurements of V V processes provide a test of the electroweak gauge structure. These precision tests are usually carried out by setting bounds on the allowed size of anomalous trilinear gauge couplings (aTGCs) [1], although several other ideas have been proposed to study effects due to BSM physics with V V final states [2][3][4][5][6][7][8][9][10][11][12][13]. Diboson production is also a background for several searches, notably those involving an heavy resa e-mail: mauro.chiesa@lapth.cnrs.fr (corresponding author) b e-mail: carlo.oleari@mib.infn.it c e-mail: emanuele.re@lapth.cnrs.fr onance decaying to a pair of gauge bosons.…”

“…Dedicated studies of pp → V V production at NLO-QCD+PS, with full leptonic decays and including resonant and non-resonant diagrams as well as spin correlations and off-shell effects exactly, were performed in Ref. [10,11,[57][58][59][60][61]. Notably, starting from the NLO+PS merging of pp → W + W − and pp → W + W − + j [62] obtained through the MiNLO approach [63], NNLO-QCD+PS results for the pp → W + W − process were obtained in Ref.…”