Cosmic‐Ray Showers Provide Strong Evidence of Neutrino Flavor Oscillation

To prolonged ovation at the recent Neutrino '98 conference in a ski resort west of Tokyo, the Japanese‐American Super Kamiokande collaboration reported by far the most convincing evidence to date of oscillatory metamorphosis between different neutrino flavors. Super Kamiokande is the gargantuan 50‐kiloton water‐Cerenkov neutrino detector buried 1 kilometer under a mountain not far from the conference site. The collaboration is headed by Yoji Totsuka of Tokyo University's Institute for Cosmic Ray Research.