Neutrinos: Window On the Universe

The observation that neutrinos change from one flavor to another as they propagate, or "neutrino oscillation", has been one of the most surprising results in particle physics in the last two decades. Through neutrino oscillation, we now know neutrinos have a small but non-zero mass, which has wide ranging implications for astrophysics, and cosmology. The T2K experiment studies neutrino oscillation by using a>99.5% pure beam of muon neutrinos sent through Japan. This seminar will describe the recent T2K results on electron neutrino appearance and muon neutrino disappearance in a muon neutrino beam. The T2K results are the first step toward future long baseline based searches for CP violation with neutrinos. Insight into the challenges of such a program will also be discussed.