T2K Finds Evidence For Muon Neutrino Oscillation

It is unfortunately that the recent earthquake in Japan disrupted the T2K experiment, especially at J-PARC, or they would have had an even stronger evidence for this. Still, based on what they already have, this collaboration found strong evidence for muon neutrino changing flavor into electron neutrino.

Now, researchers at J-PARC have made a step towards measuring the final mixing angle – theta-13 – by measuring muon neutrinos oscillating into electron neutrinos. From January 2010 until March this year, the SuperKamiokande detector observed 121 neutrinos that clearly originated from the J-PARC neutrino beam. The background signal, which could mimic a signal from electron neutrinos that are present anyway, was estimated to be around 1.5 events. However, over 13 months, researchers at T2K, which has more than 500 researchers from 12 countries, spotted six events arising from muon neutrinos turning into electron neutrinos. The probability of observing, by chance, six events when only 1.5 are expected is 0.7%, or a little less than 1 in 100.

Hopefully, they get back online at the end of the year as expected.

Zz.