Archived
This content is available here strictly for research, reference, and/or recordkeeping and as such it may not be fully accessible. If you work or study at University of Kentucky and would like to request an accessible version, please use the SensusAccess Document Converter.
Author ORCID Identifier
Date Available
7-27-2020
Year of Publication
2020
Document Type
Doctoral Dissertation
Degree Name
Doctor of Philosophy (PhD)
College
Arts and Sciences
Department/School/Program
Physics and Astronomy
Faculty
Dr. Susan Gardner
Faculty
Dr. Christopher Crawford
Abstract
A violation of mirror symmetry in the $\eta\to\pi^+\pi^-\pi^0$ Dalitz plot has long been recognized as a signal of C and CP violation. In this thesis, we show how the isospin of the underlying C- and CP-violating structures can be reconstructed from their kinematic representation in the Dalitz plot. Our analysis of the most recent experimental data reveals, for the first time, that the C- and CP-violating amplitude with total isospin I = 2 is much more severely suppressed than that with total isospin I = 0.
In searching for C- and CP-violating sources beyond the SM, we enumerate the leading-dimension, CP-violating effective operators that share the gauge symmetry and particle content of the Standard Model (SM), carefully separating the operators that are P-odd from those that are C-odd below the electroweak scale. The P-odd and CP-odd effective operators that generate permanent electric dipole moments have been the subject of much investigation in the literature; we now focus on C-odd and CP-odd operators and study their effects systematically. We emphasize that while for flavor-changing interactions the C-odd and CP-odd operators appear in mass dimension 6, for flavor-conserving interactions the C-odd and CP-odd operators appear in mass dimension 8, though some operators can be of mass dimension6 in numerical effect. In the flavor-changing case, the C-odd and CP-odd operators and P-odd and CP-odd operators probe different linear combinations of common low-energy coefficients in SM effective field theory. Remarkably, however, in the flavor-conserving case, we find that low-energy coefficients probed by a P-odd and CP-odd observable, such as by the permanent electric dipole moment of the neutron, and by a C-odd and CP-odd observable, as probed by mirror symmetry breaking in the $\eta\to \pi^+ \pi^- \pi^0$ Dalitz plot, can be completely different.
Finally, from the C-odd and CP-odd flavor-conserving operators, we determine the operators with definite isospin that can contribute to $\eta\to\pi^+\pi^-\pi^0$ decay. We illustrate how these operators can be represented in chiral perturbation theory, for the eventual determination of their contribution to mirror-symmetry breaking in the $\eta\to\pi^+\pi^-\pi^0$ Dalitz plot.
Digital Object Identifier (DOI)
https://doi.org/10.13023/etd.2020.388
Funding Information
This research was partially supported by the Department of Energy Office of Nuclear Physics under contract DE-FG02-96ER40989, 2015 -- 2019.
Recommended Citation
Shi, Jun, "Theoretical Studies of C and CP Violation in $\eta \to \pi^+ \pi^- \pi^0$ Decay" (2020). Theses and Dissertations--Physics and Astronomy. 74.
https://uknowledge.uky.edu/physastron_etds/74
