Status and neutrino oscillation physics potential of the Hyper-Kamiokande Project in Japan

Hyper-Kamiokande (Hyper-K), a proposed one-megaton water Cherenkov detector to be built in Japan, is the logical continuation of the highly successful program of neutrino (astro)physics and proton decay using the water Cherenkov technique. In its baseline design, the Hyper-K detector consists of two cylindrical tanks lying side-by-side, the outer dimensions of each tank being 48m x 54m x 250m. The inner detector region will be instrumented with 99,000 20-inch photo-sensors. An international proto-collaboration has been intensively working on the R&D of key components such as optimization of cavern, tank construction, development of high performance photo-sensors, design of new near detectors and improvements to the J- PARC neutrino beam. Hyper-K will study the CP asymmetry in neutrino oscillations using the neutrino and anti-neutrino beams produced at J-PARC. With an exposure of 7.5 MWx10^7 seconds, CP violating parameter delta can be measured to better than 19 degrees at all values of delta, and CP violation can be detected with more than 3 sigma signi cance for 76% of the values. An overview of the status of project and the studies of the sensitivity of this detector to physics quantities governing neutrino oscillation is presented.