![]() In this letter, we provide results for the \(W^ Z\) channel using the same fiducial cuts and reference frame as ATLAS. Our study closes the gap by including the NLO QCD and EW corrections in the DPA for the three-lepton channels, separating the polarization states at the amplitude level. , but is still lacking the NLO EW corrections, contrary to the four-lepton channel. ![]() ![]() This study has been performed at NLO QCD in Ref. In order to do it is necessary to study three-lepton production in the double-pole approximation (DPA) where the production and decay amplitudes are calculated in the on-shell approximations, and then combined using a sum over all polarizations retaining the full phase-space in the gauge boson propagators. The latter studies have introduced in particular the concept of fiducial polarization observables constructed out of the final-state angular observables in the fiducial volume, including the experimental cuts, but they have not investigated the separation of polarization states at the amplitude level. The EW corrections have been calculated in detail in Refs. On the theory side, the study of gauge boson polarizations effects started in the eighties and the NLO QCD corrections were included in Ref. Footnote 1 Notably, ATLAS presented in 2019 results for angular observables with 13 TeV data in the WZ channel. , while the consistent matching of NLO QCD EW corrections has been performed in Ref.Īs more data is available, there is a growing interest in the study of the polarization of the gauge bosons in the three-lepton channel. Parton shower effects have also been calculated at NLO QCD, later extended to include SM effective field theory effects in Refs. QCD precision has reached the next-to-next-to-leading order (NNLO) accuracy and a combination of NLO EW and NNLO QCD corrections has been performed in Ref. In 2018 these calculations have been extended to include anomalous couplings effects at the NLO QCD EW accuracy as well. The full NLO QCD predictions including full off-shell and spin-correlation effects for leptonic final states can be numerically calculated with the help of public computer programs such as MCFM or VBFNLO. , showing in particular the importance of the quark-photon induced correction. The NLO EW corrections were presented in Refs. The next-to-leading order (NLO) QCD corrections were calculated in Refs. Higher order QCD and EW corrections to three-lepton production in the WZ channel have reached a high precision. The latest measurements from ATLAS and CMS collaborations in the three-lepton channel can be found in Refs. With 13 TeV data as well as with new data coming from run 3 and beyond in the next years, it is possible to study non-trivial observables such as the polarization of the gauge bosons, in particular in the four-lepton channel via ZZ production and in the three-lepton channel via WZ production. ![]() The detailed study of their properties allows theorists and experimentalists for probing deeply the Standard Model (SM) and in particular the EW symmetries, as well as for searching for potential new-physics effects signaled by deviations from SM expected shapes in various observables. The CERN Large Hadron Collider (LHC) has been operating since 2009 and has accumulated lots of data, in particular in the production of W and Z electroweak (EW) gauge bosons. ![]()
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