The T2K collaboration is releasing the latest results on electron neutrino appearance, starting with the European Physical Society meeting today. This includes 2013 data taking at 220 kW and a world-record 1.2e14 protons-per-pulse.
In the new data we found 28 single-ring quasi-elastic electron neutrino candidates over an expected background of 4.6 events from the trace of electron neutrinos in the beam and mistaken neutral current interactions. For the value of θ13 from reactor experiments we expected about 20 events, so our expected significance is greater than 5 sigma. These recent results clearly establish the phenomenon of electron neutrino appearance in neutrino oscillations. The figure below shows the distribution of electron neutrino energies for the 28 events.
The T2K collaboration accompanied this new report with a press release that can be found here: http://t2k-experiment.org/2013/07/new-results-from-t2k-conclusively-show-muon-neutrinos-transform-to-electron-neutrinos/.