Pinning Down The Smallest Kind of Neutrino Oscillation

Kam-Biu Luk

University of California, Berkeley


Lawrence Berkeley National Laboratory

Neutrinos are supposed to be massless in the Standard Model of particle physics for several decades. However, a series of experiments has recently provided compelling evidences for a new phenomenon, neutrino oscillation, that implies the three types of neutrinos observed in laboratories do have mass after all. Neutrino oscillation can be described with a set of three neutrino-mixing angles, of which the smallest one called θ 13 was unknown until recently. One approach for determining θ13 is to utilize a running nuclear reactor which is a copious source of low-energy electron antineutrinos. In this talk, the recent discovery of a new kind of neutrino oscillation due to a non-zero value of θ13 observed in reactor-based experiments will be presented. The implications of this surprising observation will also be highlighted.