2006/07/31 by Kaoru Hagiwara, Naotoshi Okamura, Ken-ichi Senda · 3 citations
Physics and Astronomy · #Dark Matter and Cosmic Phenomena #Neutrino Physics Research #Particle physics theoretical and experimental studies #hep-ph
paper · pdf · doi:10.1103/physrevd.76.093002
published as Phys.Rev.D76:093002,2007
arxiv created 2007/07/10 · openalex publication_date 2007/11/13 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/30
We study the physics potential of placing a far detector in the east coast of Korea, where the off-axis neutrino beam from J-PARC at Tokai village for the Tokai-to-Kamioka project has significant intensity at a few GeV range. In particular, we examine the capability of determining the mass hierarchy pattern and the CP phase of the lepton-flavor-mixing matrix when a 100 kt water \ifmmode \checkC\else \vC\fierenkov detector is placed at various locations in Korea for the off-axis beam (OAB) of 2.5\ifmmode^∘\else\textdegree\fi and 3.0\ifmmode^∘\else\textdegree\fi at the Super-Kamiokande site. The best results are found for a combination of 3.0\ifmmode^∘\else\textdegree\fi OAB at SK (L=295 km) and 0.5\ifmmode^∘\else\textdegree\fi OAB at L=1000 km, where the mass hierarchy pattern can be determined at 3\ensuremathσ level for sin22\ensuremathθRCT\ensuremath\gtrsim0.05 (0.06) when the hierarchy is normal (inverted), after 5 yr of running (5\ifmmode×\else\texttimes\fi1021 POT). We also find that the leptonic CP phase, \ensuremathδMNS, can be constrained uniquely, without invoking antineutrino beams, as long as the mass hierarchy pattern is determined. Those results are obtained by assuming that the charged current quasielastic events can be separated from the other backgrounds with high efficiency, the neutrino energy can be reconstructed with a hundred MeV uncertainty, and the earth matter density along the baseline can be determined with 3% accuracy.