Comprehensive Analysis of Neutrinos in SK part I --Directions of the   Incident Neutrinos and the Produced Leptons--
  Super-Kamiokande collaboration assumes that the direction of every observed lepton coincides with the incoming direction of the incident neutrino, which is the fundamental basement throughout all their analysis on neutrino oscillation. We examine whether this assumption to explain the experimental results on neutrino oscillation is theoretically acceptable. Treating every physical process concerned stochastically, we have examined if this assumption just cited is acceptable. As the result of it, we have shown that this assumption does not hold even if statistically. 
E. Konishi (1), Y. Minorikawa (2), V.I. Galkin (3), M. Ishiwata (4),   I. Nakamura (4), N. Takahashi (1), M. Kato (5) and A....