Observation of entangled top quarks at the Large Hadron Collider

by Andrea Helen Knue (TU Dortmund)

Tuesday 28 Jan 2025, 16:15 → 17:15 Europe/Berlin

ENC-D308

While the existence of the top quark is a known fact today, it can only be studied since a relatively short time. After the discovery of the $b$-quark in the 1970s, a discovery of its weak-isospin partner was expected to happen in the following years. Due to the unique properties of the top quark, however, it took almost twenty years until it was finally found.
Since its discovery, its properties have been scrutinised in detail and were measured to high precision in recent years. In this presentation, it will be shown how top-antitop quark pairs can be used as a laboratory to understand fundamental properties of quantum mechanics. One of these properties is the entanglement between two particles. If two top quarks are entangled, the quantum state of one top cannot be described independently from the state of the antitop quark. The entanglement between two top quarks was recently observed at the Large Hadron Collider (LHC) at both the ATLAS and CMS experiments, and their findings will be discussed in this seminar.