CP symmetry measurement in neutrino oscillations in the T2K experiment

by Marcela Batkiewicz-Kwasniak (IFJ PAn)

Thursday 27 May 2021, 11:00 → 13:00 UTC

The charge-conjugation and parity-reversal (CP) symmetry connects particles to their antiparticles with reversed helicity. CP symmetry violation is one of the three Sakharov conditions necessary to explain the dominance of matter observed in the Universe. CP violation in the quark sector is too small to explain it, and CP violation in the lepton sector has not been conclusively observed so far. T2K is a long-baseline neutrino experiment conducted in Japan, which studies the oscillations of muon (anti)neutrinos into electron (anti)neutrinos at a distance of 300 km between the so-called near (at J-PARC) and far (SuperKamiokande at Kamioka) detectors. In April 2020, T2K published the best constraint so far on the delta_CP parameter, describing the CP symmetry conservation/violation in the neutrino oscillations, excluding the CP conservation at the 90% level. I will show the latest T2K neutrino oscillation results and present the current status of the work performed for the second phase of the T2K experiment, and the status of the T2K successor - the Hyper-Kamiokande experiment, which is expected to confirm the CP violation at the 5 sigma level. I will also discuss the IFJ involvement in T2K, its upgrade, and in the Hyper-Kamiokande project.

2021_05_27_ifj.pdf