Atmospheric Neutrino Oscillations in Three-Flavor Neutrinos. II

Abstract

We analyze the atmospheric neutrino experiments of SuperKamiokande (535 days) using the three-flavor neutrino framework with the mass hierarchy m_1 nearly equal m_2 << m_3. We study the event ratios of sub-GeV, multi-GeV and upward through-going muons zenith angle distributions. Taking into account the atmospheric and terrestrial experiments, we obtain the allowed regions of mass and mixing parameters Δm_{12}^2, sin^22θ_{12}, Δm_{23}^2, θ_{13} and θ_{23}. The mass parameter Δm^2_{23} is restricted to 0.01eV^2-0.0002eV^2. For mixing parameters, there is no difference between the large θ_{12} angle solution and the small one, and θ_{13}<13degrees, 28degrees<θ_{23}<37degrees and 53degrees< θ_{23}<62degrees for Δm_{23}^2=0.01eV^2, θ_{13}<23degrees and 29degrees<θ_{23}<61degrees for Δm_{23}^2=0.00eV^2, 4degrees< θ_{13}<22degrees and 38degrees<θ_{23}<54degrees for Δm_{23}^2 =0.0002eV^2.