Charlie Chen
- MSc (McGill University, 2019)
- BSc (McGill University, 2017)
Topic
Differential cross-section measurements of WbWb production in the lepton+jets channel at sqrt{s}=13 TeV with the ATLAS detector
Department of Physics and Astronomy
Date & location
- Friday, August 9, 2024
- 2:00 P.M.
- Clearihue Building, Room B017
Examining Committee
Supervisory Committee
- Dr. Robert Kowalewski, Department of Physics and Astronomy, University of Victoria (Supervisor)
- Dr. Robert McPherson, Department of Physics and Astronomy, UVic (Member)
- Dr. Henning Struchtrup, Department of Mechanical Engineering, UVic (Outside Member)
External Examiner
- Dr. Matthew Jones, Department of Physics and Astronomy, Purdue University
Chair of Oral Examination
- Dr. Cedric Littlewood, Department of Greek and Roman Studies, UVic
Abstract
The top quark provides a unique opportunity to test the Standard Model of particle physics. Its heavy mass causes it to decay before it can hadronize, allowing for the study of the properties of a bare quark. This thesis presents differential cross-section measurements stemming from various top quark processes. This measurement is conducted in the presently uncovered semileptonic channel, where one W boson decays leptonically and the other decays hadronically. The analysis is motivated by the need to improve the modeling of the interference effects between singly-resonant and doubly-resonant top quark decays. This effect has been the source of significant modeling uncertainties in other top-sector analyses. The data and simulation used to perform this analysis correspond to the full ATLAS Run 2 dataset, collected 2015-2018. This data corresponds to an integrated luminosity of 139 fb-1 and a center of mass energy of √𝑠=13 TeV. The measured cross-sections are compared to predictions using different combinations of MC generators. Together with a complementary analysis in the dileptonic channel, this thesis provides a means to constrain modeling uncertainties towards the development of an all-inclusive bb4l generator. This generator could model all top quark processes while accurately accounting for all interference effects.