Highlights from T2K

H. Niewodniczanski Institute of Nuclear Physics PAN, Cracow, Poland

^a e-mail: Anna.Dabrowska@ifj.edu.pl

Published online: 4 November 2016

Abstract

T2K is a long-baseline neutrino experiment designed to measure neutrino oscillations parameters. A high-intensity beam of muon neutrinos produced at the J-PARC accelerator complex is sent towards the near detector facility (the ND280 and INGRID detectors, located 280 m away from the neutrino source) and the far detector, Super-Kamiokande (295 km away). The change in the measured intensity and the composition of the neutrino beam between the near and far detectors are used to provide information on the oscillation parameters. T2K has delivered the world’s best measurement of the θ₂₃ angle by observing muon neutrino disappearance. It was also the first experiment to observe electron neutrino appearance (2013) with a significance of 7.3 σ, to measure the associated θ₁₃ mixing angle, and to provide the first hint of a non-zero δ_CP phase. The first running of anti-neutrinos in the T2K experiment shows a clear dip below 1 GeV, as expected for an oscillation signal. The T2K experiment is also capable of providing information on neutrino-nucleon cross sections at energies around 1 GeV, thanks to a large amount of target material present in the near detector facility.

A summary of the recent oscillation measurements as well as selected cross section results are presented.