Phenomenology of atmospheric neutrinos

Author(s)

Diego Rossi Gratieri

• Document type: Master's Dissertation
• Press: Campinas, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Instituto de Física Gleb Wataghin
• Defense date: 2006-03-27

Examining board members

Orlando Luis Goulart Peres; Carola Dobrigkeit Chinellato; Juan Carlos Garcia

• Advisor: Orlando Luis Goulart Peres

Abstract

In this work we try to understand the phenomena of neutrino oscillations,and use this to describe more precisely the atmospheric neutrino data.Our main motivation is to describe the excess of events of electron-neutrino type found in the SuperKamiokande results at low energies when compared with the predictions of the two-generation neutrino oscillation which solves the problem of the up-down muon neutrino asymmetry very successfully To do this we generalize the oscillationmodel from two to three neutrino flavors,opening the possibility of oscillation between the electron neutrino type and the others.Then we obtain a semi-analytic solution of the three flavors problem using the neutrino phenomenological limits on oscillation parameters,squared masses differences and mixing angles.We also take into account matter effects on the electronic neutrino when it crosses the Earth and has it ¿s oscillation pattern changed (AU)