Analysis Tool for Atmospheric Neutrino Oscillations

Of all the neutrino oscillation data, the atmospheric data is statistically the most important. It is also the most complex to analyze. This is because the source is cosmic rays colliding with the atmosphere or the rock in the Earth and, most importantly, Super‐K is the only experiment in which the angle of the neutrino is approximately determined by a measurement of the direction of the created and measured lepton. For pedagogic purposes, we first derive how such an analysis is done. We then derive a new computationally efficient but still quantitative way of doing the analysis and we present some results for a two neutrino model.