The JHF-Kamioka neutrino experiment

Abstract

We propose the JHF-Kamioka neutrino experiment to study the mass and mixing of leptons to great precision through neutrino oscillation. The experiment uses a high intensity narrow-band neutrino beam produced by JHF, Japan Hadron Facility, and the world largest water Cherenkov detector, Super-Kamiokande. The main physics goals are: (1) to discover ν μ→ν e oscillation with a mixing angle, θ 13, down to 0.006, (2) to measure the oscillation parameters in ν μ→ν μ oscillation with a precision of 1% for the mixing angle and 10 −4eV 2 for the mass square difference, and (3) to confirm ν μ→ν τ or to eliminate ν μ→ν s by measuring the neutral current events. The experiment can extend the physics potential to measure CP violation in neutrino oscillation for the CP-violation phase ( δ) down to 10–20°, by upgrading the JHF accelerator to 4 MW and by constructing a new 1 Mton water Cherenkov detector, Hyper-Kamiokande. The experiment is planned to start in 2007 at the same time of completing the JHF accelerator complex.