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Solving the neutrino parameter degeneracy by measuring the T2K off-axis beam in Korea

Kaoru Hagiwara·Naotoshi Okamura·Ken-ichi Senda
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Abstract

The T2K neutrino oscillation experiment will start in 2009. In this experiment the center of the neutrino beam from J-PARC at Tokai village will go through underground beneath Super-Kamiokande, reach the sea level east of Korean shore, and an off-axis beam at $0.5^{\circ}$ to $1.0^{\circ}$ can be observed in Korea. We study physics impacts of putting a 100 kt-level Water \cerenkov detector in Korea during the T2K experimental period. For a combination of the $3^{\circ}$ off-axis beam at SK with baseline length L = 295 km and the $0.5^{\circ}$ off-axis beam in the east coast of Korea at L = 1000 km, we find that the neutrino mass hierarchy (the sign of $m^2_{3} - m^2_1$) can be resolved and the CP phase of the MNS unitary matrix can be constrained uniquely at 3-$σ$ level when \sin^2 2θ_{\rm rct} $ \ge 0.06 $.

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Kaoru Hagiwara, Naotoshi Okamura, Ken-ichi Senda. 2005-12-31. Solving the neutrino parameter degeneracy by measuring the T2K off-axis beam in Korea. https://doi.org/10.1016/j.physletb.2006.04.041%2010.1016%2Fj.physletb.2006.09.003

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