Neutrino oscillations discovered in 1998 by the Super-Kamiokande experiment is an very interesting physics subject to probe the property of neutrinos. With the discovery, Prof. Takaaki Kajita in the Super-Kamiokande collaboration and Prof. Art McDonald in the SNO collaboration were awarded the Novel prize in Physics in 2015.
In this colloquium, we will introduce the basic property of neutrinos and the history of the discovery first. After the introduction, we explain the modern accelerator experiments to study neutrino oscillations.
In Japan, the world-highest power proton accelerator named J-PARC was built in 2009, and we are conducting the neutrino experiment, T2K, by using the accelerator neutrino beam from J-PARC to Super-Kamiokande.
In the experiment, we may find an interesting phenomena, a violation of the symmetry between a particle and the anti-particle. The violation of the symmetry between a particle and the anti-particle is called CP violation.
Physicists consider that the CP violation is one of the key processes to make our universe only with matter.
We also report neutrino CP violation in the colloquium.