Precision Constraints of Electroweak Decays of Hadrons with Lattice QCD
Files
(Library staff access only.)
Date
2024
Authors
Smail, Rose Eden
Editors
Advisors
Zanotti, James
Young, Ross
Young, Ross
Journal Title
Journal ISSN
Volume Title
Type:
Thesis
Citation
Statement of Responsibility
Conference Name
Abstract
This thesis investigates the precision calculations of hadronic decays, focusing on nucleon isovector charges, charge symmetry violation in the axial charge of the nucleon, and radiative corrections in pion decay using advanced lattice quantum chromodynamics techniques. Employing the Feynman-Hellmann theorem and a flavour symmetry breaking approach, we calculate the axial, tensor, and scalar isovector charges of nucleons and hyperons, achieving approximately 2% precision for the tensor charge gT while highlighting the need for further refinement in the scalar charge gS and axial charge gA. This comprehensive analysis allows us to derive estimates of charge symmetry violation in the nucleon axial charge, resulting in a quantitative determination of systematic uncertainties. We introduce a novel method to compute radiative corrections to pion leptonic decay rates within a QCD+QED framework. Our findings on the radiative correction δπ are consistent with theoretical expectations and comparable to prior studies; however, they still necessitate extrapolation to the physical pion mass and continuum limits. Overall, this research significantly enhances our understanding of hadronic decays, revealing critical aspects of weak interactions and their implications for the Standard Model, as well as potential physics beyond it.
School/Discipline
School of Physics, Chemistry and Earth Sciences : Physics
Dissertation Note
Thesis (Ph.D.) -- University of Adelaide, School of Physics, Chemistry and Earth Sciences : Physics, 2025
Provenance
This thesis is currently under embargo and not available.