Andrew Pilkington (Manchester)

The Force Aweakens: searching for new sources of CP violation in the electroweak sector

Abstract: The matter-antimatter asymmetry in the Universe can only be explained if there are new sources of CP-violation, i.e. beyond those observed in the quark sector of the Standard Model. These new sources can induce anomalous Higgs boson interactions and anomalous weak-boson self-interactions. Whilst the search for CP-violating effects in the Higgs boson interactions is well established at the Large Hadron Collider, there has been surprisingly little attention paid to the weak-boson self-interactions. In this seminar, I will discuss a new measurement programme at will utilise diboson data and vector boson scattering processes to set the best constraints on the new sources of CP violation. In particular, the first ATLAS measurement of a CP-sensitive observables (in the electroweak Zjj final state) will be discussed, along with a new analysis technique that allows CP-sensitive observables to be constructed using machine learning algorithms.