Introdução à física de neutrinos

Abstract

Neutrino physics arose with Pauli's proposal for a third particle as a solution to the beta decay based on energy and momentum conservation arguments. Since then, the sources and three flavours of neutrinos has been widely studied in order to understand all the features of these particles. This work has the goal of giving an overview about each neutrino of the standard model and previously works that tried to better understand it. In the first chapter we review the history of neutrino physics. In the second chapter we will give a qualitative introduction about the two discrete symmetries CP, later we will give the main differences between helicity and chirality, lastly we will deal with the structure of the standard model and how to build the weak sector. In the third chapter we study how the neutrinos were detected, and provide a mathematical treatment about neutrino oscillations with N flavors and analyze graphically the case of two flavors, we finish with a discussion about some experiments that support this theory. In the fourth chapter we perform a non sophisticated analysis about some experiments that give an upper limit on neutrino's masses. In the fifth chapter we deal with some differences between Dirac and Majorana equations and we will do a relation between neutrinos and these equations. In our final considerations we treat about some aspects of neutrinos oscillation in matter that can be performed in future.