Anomalous triple gauge couplings at the large hadron collider

Abstract

While we are verifying with high precision that matter behaves as predicted by the Standard Model at the Large Hadron Collider (LHC), we expect that physics beyond the Standard Model (BSM) presents at a more microscopic scale. In presence of a large mass gap between the electroweak and BSM scales, the Standard Model Effective Field Theory (SMEFT) provides the systematic framework to parametrize the effects of BSM as small modifications to the interactions between the fundamental particles of the Standard Model. Among SMEFT effects, anomalous triple gauge couplings (aTGCs) would imply interactions involving three gauge particles that do not follow the Standard Model. aTGCs have a distinctive theoretical feature that the interference between SM and dimension-6 term, the lowest order in the SMEFT expansion is suppressed, complicating the measurement of the dimension-6 effect without the dimension-8 corrections. Therefore, a method to recover interference is necessary, such as observing the full process that incorporates either the decay or emission of gauge particles. In this thesis, we propose the Vector Boson Fusion (VBF) as a collision process where the interference can be recovered. The interference resurrection in VBF is established through analytical calculations, and the resulting expected precision of aTGC measurements is numerically estimated.