Masato Shiozawa (Project Leader of Hyper-Kamiokande)
Shigetaka Moriyama (Technical Coordinator)
Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo
Abstract: The Super-Kamiokande detector has been providing fascinating results in particle physics and astrophysics over more than 20 years, most notably the discovery of neutrino oscillation which was awarded the 2015 Nobel Prize in Physics. The Hyper-Kamiokande or Hyper-K, as a straightforward extension of the Super-Kamiokande, will provide major new capabilities to make new discoveries in particle and astroparticle physics thanks to an order of magnitude increase in detector mass and improvements in photon-detection system along with the envisioned J-PARC Megawatt-class neutrino beam. The Hyper-K and J-PARC neutrino beam measurement of neutrino oscillation is more likely to provide a 5-sigma discovery of CP violation than any other existing experiment. Hyper-K will also be the world leader for nucleon decays. The sensitivity to the partial lifetime of protons for the decay modes of p→ e+ π0 is expected to exceed 10^35 years. Finally, the astrophysical neutrino program involves precision measurement of solar neutrinos and their matter effects, high-statistical Supernova burst and Supernova relic neutrinos. The Hyper-K is expected to start operation in 2027.
Abstract: Hyper-Kamiomande (HK) is a next generation multi-purpose large-scale water Cherenkov detector. Among the broad physics program of HK, one major target is a search of as-yet unmeasured CP violation in neutrino sector by the long-baseline project. HK will act as the far detector to measure neutrino beam produced at J-PARC, 295km away from HK. 500kW proton beam at J-PARC, which is producing high intensity neutrino beam for T2K, will be upgraded to 1.3MW for HK. The combination of HK and 1.3MW beam will provide unprecedented high statistics of the neutrino and antineutrino signals to measure the CP violation and reveal a full picture of neutrino mixing. In order to minimize the systematic uncertainties due to the modeling of the neutrino flux and interactions, a suite of new near detectors is planned by international collaboration.
This talk will highlight the prospects of HK long-baseline project and the challenge of the near detectors, including a new intermediate Water Cherenkov detector.