Tatsu Takeuchi (Virginia Tech)

Matter Effect from Non-Standard Interactions of the Neutrino

Neutrino oscillation in matter is sensitive to interactions between the neutrinos and the matter particles, including the Standard Model W-exchange interaction and any Non-Standard Interactions (NSI's) that the neutrinos may have. In this talk. I will show how the Jacobi method can be utilized to find analytical expressions for the effective mixing angles and effective CP violating phase of the neutrinos in matter, which lead to extremely simple and compact expressions for the oscillation probabilities. All matter effects can be absorbed into the "running" of the effective parameters. It will be shown that the SM interactions cause theta12 and theta13 to run, while NSI's involving the mu and tau neutrinos cause theta23 and delta to run. By looking at the "running" of the effective parameters, it is possible to find the best conditions under which the NSI effects will be manifest.