Javier Caravaca

Sterile neutrino searches at the T2K experiment

Neutrino oscillations have been well-stablished by many experiments since their discovery in 1998. Nevertheless, there are some anomalies not explainable by the standard three neutrino oscillation model. They are short base-line neutrino experiments that measure a different neutrino interaction rate than expected, like the so-called reactor and gallium anomalies. This might be the hint of the existence of a fourth neutrino type, with a mass of the order of 1eV, that wouldn't feel the weak force and hence it is called 'sterile neutrino'. The near detector (280m baseline) of the T2K experiment (ND280) has searched for electron-neutrino oscillation to sterile neutrino (electron-neutrino disappearance channel) in an electron-neutrino flux peaked at a neutrino energy of 500MeV. I will present the analysis and the latest results after a brief introduction to neutrino oscillations and sterile neutrinos.