IPNS Physics and J-PARC Seminar : First results from the joint oscillation analysis between SK atmospheric neutrinos and T2K accelerator neutrinos


2023/12/20 16:00 – 17:00


Tokai-1 Building Room 116 and Zoom


Lukas BERNS (Tohoku University)






The T2K experiment studies the oscillations of a high-power muon neutrino beam generated at J-PARC and measured at the Super-Kamiokande (SK) detector 295 km away. Many results have been presented using data collected until 2020, including world first indications of leptonic CP violation. The experiment is entering a new phase toward the discovery of CP violation with upgraded accelerator and beam line for higher power, an upgraded near detector for better flux and interaction constraints and enhanced sensitivity at the SK detector. In parallel, the T2K and SK collaborations have been developing a new joint analysis of accelerator and atmospheric neutrino data for more precise constraints on neutrino oscillation parameters. Because of differences in neutrino energies and oscillation baselines, a joint analysis can break degeneracies between oscillation parameters present in the individual analyses and is expected to improve the sensitivities beyond simple increase in statistics. Here we present a new result from a joint analysis of T2K data collected until 2020 and SK-IV data, using a specifically developed systematic uncertainty model that includes correlations between the two experimental datasets.

Release date 2023/12/04 Updated 2024/05/23