Neutrino oscillation at T2K: a Bayesian perspective

by Dr Kirsty Duffy

T2K is a long-baseline neutrino oscillation experiment, which studies neutrino oscillation in two channels: disappearance of muon neutrinos and appearance of electron neutrinos. Roughly equal amounts of data have been collected using both a neutrino-enhanced and an antineutrino-enhanced beam, which allows the oscillation of neutrinos and antineutrinos to be compared. Using this data, T2K recently released the first ever experimental result to disfavour CP conservation in the neutrino sector at 90% probability.

This analysis relies heavily on Bayesian statistical methods, particularly the numerical Markov Chain Monte Carlo technique. This seminar will motivate and present these methods, both in the case of T2K and the broader comparison to the frequentist statistical interpretation. Specific examples from the T2K analysis will be used to illustrate the treatment of nuisance parameters, credible intervals and interpretation of results in the Bayesian framework, and the Markov Chain Monte Carlo method. Finally, the Bayesian results from T2K will be presented and discussed.