Neutrino oscillation experiments have shown de nite evidence for non-zero neutrino
masses. However, these experiments only tell us about neutrino mass di erences, and nothing
about the absolute masses themselves. The observation of neutrinoless double-beta (0 )
decay, a hypothetical nuclear transition, would provide the rst absolute mass scale measurement
of the neutrino outside of cosmology. This decay would imply the neutrino to be
a Majorana particle, the rst fermion of its kind. 0 decay would also be the rst observation
of lepton number violation. The Enriched Xenon Observatory (EXO) is currently
searching for 0 decay in 136Xe with a half-life greater than 1025 years.
EXO-200 is the rst experiment of the EXO physics program, which has observed twoneutrino
double beta decay (2 ) in 136Xe for the rst time, with a half-life of 2:165
0:075 1021 years [1]. This is the longest measured half-life to date. EXO is now designing
a 5-tonne scale detector, nEXO, to be sensitive to the inverted-scale hierarchy. Despite the
careful selection of radiopure substances for the detector, the existence of trace levels of
222Rn is inevitable. One of the daughters of 222Rn, 214Bi, can emit photons at the Q-value
for 0 decay, making it a critical background. This dissertation investigates the method
of Rn removal from gaseous Xe through the use of a Cu wool trap.
Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:OSUL.10219/2148 |
Date | 17 March 2014 |
Creators | Beauchamp, Eric |
Publisher | Laurentian University of Sudbury |
Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
Language | English |
Detected Language | English |
Type | Thesis |
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