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We present two new extractions of the QCD coupling constant at the Z pole, $alpha_S(m_Z)$, from detailed comparisons of inclusive W and Z hadronic decays data to state-of-the-art perturbative Quantum Chromodynamics calculations at next-to-next-to-next-to-leading order (N$^{3}$LO) accuracy, incorporating the latest experimental and theoretical developments. In the W boson case, the total width computed at N$^{3}$LO is used for the first time in the extraction. For the Z boson pseudo-observables, the N$^{3}$LO results are complemented with the full two- and partial three-loop electroweak corrections recently made available, and the experimental values are updated to account for newly estimated LEP luminosity biases. A combined reanalysis of the Z boson data yields $alpha_S(m_Z) = 0.1203 pm 0.0028$, with a 2.3% uncertainty reduced by about 7% compared to the previous state-of-the-art. From the combined W boson data, a value of $alpha_S(m_Z) = 0.101 pm 0.027$ is extracted, with still large experimental uncertainties but also reduced compared to previous works. The levels of theoretical and parametric precision required in the context of QCD coupling determinations with permil uncertainties from high-statistics W and Z boson samples expected at future $e^+e^-$ colliders such as the FCC-ee, are discussed in detail.
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We review models of electroweak symmetry breaking due to new strong interactions at the TeV energy scale and discuss the prospects for their experimental tests. We emphasize the direct observation of the new interactions through high-energy scatterin
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The analysis of hadronic vector boson decays at LHC does not normally allow for interference with QCD production. These effects are studied here using the Sherpa package and can move by several GeV/c 2 the peak positions experiments would reconstruct
We compute the quark and gluon transverse momentum dependent parton distribution functions at next-to-next-to-next-to-leading order (N$^3$LO) in perturbative QCD. Our calculation is based on an expansion of the differential Higgs boson and Drell-Yan