Measuring theta?? via muon neutrino to electron neutrino oscillations in the MINOS experiment

One of the primary goals in neutrino physics at the present moment is to make a measurement of the neutrino oscillation parameter B13 . This parameter, in addition to being unknown, could potentially allow for the introduction of CP violation into the lepton sector. The MINOS long-baseline neutrino oscillation experiment has the ability to make a measurement of this parameter, by looking for the oscillation of muon neutrinos to electron neutrinos between a Near and Far Detector over a distance of 735 km. This thesis discusses the development of an analysis framework to search for this oscillation mode. Two major improvements to pre-existing analysis techniques have been implemented by the author. First, a novel particle ID technique based on strip topology, known as the Library Event Matching (LEM) method, is optimized for use in MINOS. Second, a multiple bin likelihood method is developed to fit the data. These two improvements, when combined, increase MINOS' sensitivity to sin2(W13 ) by 27% over previous analyses. This thesis sees a small excess over background in the Far Detector. A Frequentist interpretation of the data rules out B13 = 0 at 91 %. A Bayesian interpretation of the data is also presented, placing the most stringent upper boundary on the oscillation parameter to date, at sin2 (2B13 ) < 0.09(0.015) for the Normal (Inverted) Hierarchy and 6cp = 0.

Name dc:type.qualificationname

Doctor of Philosophy (PhD)

Level dc:type.qualificationlevel

Doctoral

Grantor dc:publisher.institution

University of Cambridge

Year dc:date.issued

2012

Author dc:creator

• Toner, Ruth Bushnell

Licence

• https://apollo8-f-pro.lib.cam.ac.uk/bitstreams/adc158a3-01aa-41c3-8c56-90708f676160/download
• https://www.rioxx.net/licenses/all-rights-reserved/

Language dc:language

eng

DOI dc:identifier.doi

https://doi.org/10.17863/CAM.11706

OAI identifier oai:identifier

oai:www.repository.cam.ac.uk:1810/265528