Measurement of Vector Boson Scattering in semileptonic final states with the ATLAS detector using LHC Run-2 data

This thesis presents the measurement of vector boson scattering (VBS) in semi-leptonic final states using the full Run 2 dataset (139 fb⁻¹) collected by the ATLAS detector at the LHC. VBS is a key process for probing the electroweak symmetry breaking mechanism of the Standard Model (SM) and is sensitive to new physics effects such as anomalous quartic gauge couplings. The analysis targets the electroweak production of two weak vector bosons in association with forward jets (EW VV+jj). Results are interpreted in the framework of an effective field theory with dimension-8 operators.