ABSTRACT

The Standard Model – the comprehensive theory that describes our current understanding of the electromagnetic, strong, and weak interactions is not expected to be the final theory of physics. The best experimental evidence we have for new physics beyond the Standard Model is in the neutrino sector. A solid body of evidence has accumulated through a number of experiments indicating that the different flavors of neutrino can change into each other, a phenomenon called neutrino oscillation or neutrino mixing. Neutrino oscillation is of much current interest in particle physics, more so than ever since experimental evidence at the Sudbury Neutrino Observatory (SNO) has definitively confirmed the phenomenon. Cosmic rays contain a large number of pions which preferentially decay into muons and their associated (anti)neutrinos.