Speaker
Dr
Patrick de Perio
(Columbia University)
Description
The T2K experiment is a long-baseline neutrino oscillation experiment based in Japan. An off-axis, high purity $\nu_\mu$ beam is directed towards a near detector complex (ND280), situated 280 m from the neutrino production target, and the Super-Kamiokande (SK) far detector at 295 km. This talk describes the T2K beam and detectors, including a novel optical transition radiation monitor for precisely measuring the parent proton beam in order to determine the neutrino beam direction. A framework for evaluating the uncertainties in neutrino interactions and pion hadronic interactions in ND280 and SK is presented. A new SK event reconstruction algorithm is described and the SK detector systematic errors are evaluated based on atmospheric neutrino and cosmic ray muon data. These developments are used in a Markov Chain Monte Carlo neutrino oscillation analysis of the T2K Run 1-4 data corresponding to $0.657 \times 10^{21}$ protons on target. The analysis simultaneously considers the ND280 $\nu_\mu$ samples, and SK single muon and single electron samples, producing a measurement of $\nu_\mu$ disappearance and $\nu_{\mu} \rightarrow \nu_e$ appearance, and precise estimates of neutrino oscillation parameters. Measurements of $\theta_{13}$ from reactor neutrino experiments are combined with the T2K data resulting in the first hints toward non-zero $\delta_{CP}$.
Primary author
Dr
Patrick de Perio
(Columbia University)
