Abstract:
We present a search for nonzero theta(13) and deviations of sin(2)theta(23) from 0.5 in the oscillations of atmospheric neutrino data from Super-Kamiokande I, II, and III. No distortions of the neutrino flux consistent with nonzero theta(13) are found and both neutrino mass hierarchy hypotheses are in agreement with the data. The data are best fit at Delta m(2) = 2.1 x 10(-3) eV(2), sin(2)theta(13) = 0.0, and sin(2)theta(23) = 0.5. In the normal (inverted) hierarchy theta(13) and Delta m(2) are constrained at the one-dimensional 90% C.L. to sin(2)theta(13) < 0.04(0.09) and 1.9(1.7) x 10(-3) < Delta m(2) < 2.6(2.7) x 10(-3) eV(2). The atmospheric mixing angle is within 0.407 <= sin(2)theta(23) <= 0.583 at 90% C.L.
