Measurements of the Standard Model Higgs boson in the WW decay mode with the ATLAS detector

Thesis

The discovery of a Standard Model-like Higgs boson in July 2012 signalled the beginning of a new realm of high energy physics research at the CERN Large Hadron Collider. The decade since has involved studying this new particle in several final states and in challenging kinematic regimes. Measurements are performed with increasing precision, which help to understand the Higgs boson and its role within the Standard Model of particle physics, narrowing down the possible existence of new physical phenomena.

This thesis presents measurements of the Standard Model Higgs boson production cross sections through gluon-gluon fusion and vector-boson fusion using the H→WW decay mode. The measurements are performed with a data set collected from proton-proton collisions occurring at √s=13 TeV by the ATLAS detector during Run 2 of the Large Hadron Collider (2015–2018), corresponding to an integrated luminosity of 139 fb^-1. Given the size of the Run 2 data set, the measurements are extended to measure production cross sections of the Higgs boson in distinct kinematic fiducial regions using the Simplified Template Cross Section framework. Good agreement with the predictions of the Standard Model are observed within the uncertainty of the measurements.

Authors: Smith, HA

• DOI: 10.5287/ora-qx5woq4dz
• Type of award: DPhil
• Level of award: Doctoral
• Awarding institution: University of Oxford
• Language: English
• Keywords: Particle Physics; ATLAS; STXS; W bosons; Higgs boson
• Subjects: Particle Physics