Special Colloquium "Tracking the Higgs boson: improving particle reconstruction and exploring new physics frontiers through Higgs boson self-interactions" by Sebastien Rettie (CERN)

Friday 19 Apr 2024, 10:00 → 11:00 Europe/Amsterdam

Veltman center (H331) (Nikhef)

The landmark discovery of the Higgs boson at the Large Hadron Collider (LHC) in 2012 heralded the start of a new era in particle physics. A detailed study of this particle will allow us to map out the mechanism by which matter acquires mass in the early Universe, known as the Higgs mechanism. Characterizing the Higgs mechanism is crucial not only to understanding the early formation, evolution, and fate of the Universe, but it also enables us to answer several big open questions in physics. One key parameter to the Higgs mechanism that remains unknown is whether the Higgs boson interacts with itself —in other words, measurement of the Higgs self-coupling. The best way to measure the Higgs self-coupling is by looking for a very rare process called di-Higgs production, whereby a pair of Higgs bosons is produced in proton-proton collisions at the LHC. This seminar will motivate and detail the latest efforts by the ATLAS collaboration at measuring this extremely rare process. In addition, I will discuss improvements to particle identification and reconstruction techniques that enhance our sensitivity to di-Higgs production by using advanced machine learning techniques. A particular emphasis will be placed on charged particle track reconstruction, or tracking, as this underpins the ATLAS reconstruction chain, providing direct benefits to di-Higgs searches and the entire ATLAS physics programme.