Please contact Beth Demkowski, demkowsk@umich.edu for Zoom link.

After a decade of operation, the T2K Collaboration published in 2020 in Nature very exciting results showing the strongest constraint yet on the parameter that governs the breaking of the symmetry between matter and antimatter using neutrino oscillations. T2K has studied how beams of muon neutrinos and antineutrinos transition into electron neutrinos and electron antineutrinos, respectively. The parameter governing the matter/antimatter symmetry breaking in neutrino oscillation, called δcp phase, can take a value from -180º to 180º. For the first time, T2K has disfavoured almost half of the possible values at the 99.7% confidence level. This outstanding result is starting to reveal a basic property of neutrinos that have not been measured until now. This is an important step on the way to knowing whether or not neutrinos and antineutrinos behave differently. In the quest of CP violation there are many challenges that compromise the performance of the T2K experiment. I will discuss the challenges and describe the possible solutions selected by the experiment to overcome these limitations.