Graduation Semester and Year
Summer 2026
Language
English
Document Type
Dissertation
Degree Name
Doctor of Philosophy in Physics and Applied Physics
Department
Physics
First Advisor
Benjamin J.P. Jones
Second Advisor
David R. Nygren
Third Advisor
Jonathan A. Asaadi
Fourth Advisor
Raquel Castillo Fernández
Fifth Advisor
Frank W. Foss Jr.
Abstract
Neutrinos are the most abundant particles in the universe that carry mass. Yet, we know very little about them since they are electrically neutral and interact weakly. A small instance after the Big Bang, an imbalance occurred that caused matter to be produced in greater quantities than antimatter. A leading candidate for this unexplained process is leptogenesis. Leptogenesis predicts that neutrinos are Majorana particles: a particle that is its own antiparticle. Today, particle detectors are being constructed to search for this property through the yet unobserved neutrinoless double beta decay (0νββ) . If observed, this would demonstrate that neutrinos are Majorana particles and help explain the matter-antimatter imbalance in the early universe.
Proposed experiments aim to increase the target isotope mass while improving background discrimination. Successfully identifying the Ba2+ daughter produced from 136Xe 0νββ decay would represent a new milestone in ultra-low background rare event searches.
This dissertation focuses on the development of ion transport and detection techniques, with the long term goal of identifying the barium daughter ion in 0νββ of 136Xe. A new type of microfabricated ion detector called νBIT is introduced, combining an optical sensing region with a radio frequency carpet on a single platform. The optical sensing region demonstrates single molecule fluorescence imaging of Ba2+ ions on microfabricated electrodes, while the radio frequency carpet successfully levitates and transports potassium ions in helium buffer gas at pressures up to 1 bar. It will also present development of a new compact ion source of Ba2+ for testing barium sensors, and novel methods of event reconstruction using diffusion in xenon time projection chambers.
These results establish key technologies required for barium tagging and provide a path toward future integrated microfabricated detectors capable of operating within high pressure xenon gas environments.
Keywords
neutrinos, neutrinoless double beta decay, time projection chamber, diffusion, barium ions, radio frequency carpets, single molecule fluorescence imaging, microfabrication, ions, ion sensing
Disciplines
Physics
License
This work is licensed under a Creative Commons Attribution 4.0 International License.
Recommended Citation
Navarro, Karen E., "Ultra-Low Noise Ion Detection for Neutrinoless Double Beta Decay Searches" (2026). Physics Dissertations. 3.
https://mavmatrix.uta.edu/physics_dissertations2/3