Imaging single barium atoms in solid xenon for barium tagging in the nEXO neutrinoless double beta decay experiment
Date
2016
Authors
Walton, Timothy, author
Fairbank, William M., advisor
Berger, Bruce, committee member
Van Orden, Alan, committee member
Wilson, Robert, committee member
Journal Title
Journal ISSN
Volume Title
Abstract
The nEXO experiment will search for neutrinoless double beta decay of the isotope 136Xe in a ton-scale liquid xenon time projection chamber, in order to probe the Majorana nature of neutrinos. Detecting the daughter 136Ba of double beta decay events, called barium tagging, is a technique under investigation which would provide a veto for a background-free measurement. This would involve detecting a single barium ion from within a macroscopic volume of liquid xenon. One proposed barium tagging method is to trap the barium ion in solid xenon at the end of a cold probe, and then detect it by its fluorescence in the solid xenon. In this thesis, new studies on the spectroscopy of deposits of Ba and Ba+ in solid xenon are presented. Imaging of barium atoms in solid xenon is demonstrated with sensitivity down to the single atom level. Achievement of this level of sensitivity is a major step toward barium tagging by this method.