Super-Kamiokande atmospheric neutrino results

We present atmospheric neutrino results from a 79 kiloton year (1289 days) exposure of the Super-Kamiokande detector. Our data are well explained by νμ → ντ 2-flavor oscillations. We have been attempting to discriminate between the possible oscillating partners of the muon neutrino as being either the tau neutrino or the sterile neutrino. Pure νμ → νs oscillation is disfavored at 99% C.L.. Moreover, we performed the appearance search for charged current tau neutrino interactions in the upward-going samples. Our data is consistent with ντ appearance at roughly the two-sigma level. Talk presented on XXXVIth Rencontres de Moriond Electroweak Interactions and Unified Theories 10-17 March 2001. Table 1: Event summary for 1289 days contained sample sub-GeV (Evis < 1.33GeV) Data MC(Honda flux) 1ring e-like 2864 2668 1ring μ-like 2788 4073 multi ring 2159 2585 Total 7811 9326 multi-GeV FC(Evis > 1.33GeV) Data MC(Honda flux) 1ring e-like 626 613 1ring μ-like 558 838 multi ring 1318 1648 Total 2502 3099 Partially Contained Total 754 1065