Differences in neutrino and anti neutrino?
Actually, you find yourself still looking for the answer to whether neutrinos are their own antiparticles. Since the same two messages come in the last week, showing evidence that neutrinos and antineutrinos behave slightly differently and are differently hard.
The first result comes from the MINOS experiment. We had it been produced by the “long-baseline” experiments, the particle accelerator at a neutrino detector and are observed at a few hundred miles away. Since we know the distance, one can count how often do neutrinos change into other neutrino. The MINOS detector at Fermilab is supplied with neutrinos. There, you shoot a beam of protons on graphite.
735 km away then started to MINOS sometimes some of these neutrinos. In the experiments we have now presented it to the mass difference between muon and tau neutrinos measured. Expressed as the square of the mass difference Δm ² obtained a value of 2.35 x 10 -3 eV ². But now the surprise – this measurement for antineutrinos ² lead to a 40% increase in Δm! Yet the statistics are not so good – the confidence in the measurement is only 95%. So – wait. The exciting result to D0 unexpectedly strong symmetrical recently is possibly even back then.
Photomultiplier in the mini-Boone tank. Photo: Fermilab Visual Media Services
The second possible surprise comes from Mini Boone, be the first stage of the experiment with an additional detector to Boone. This experiment is repeated but in fact a surprise, which occurred in 1990 in Los Alamos at LSND. In studies of the conversion of (anti) muon neutrino into (anti) electron neutrinos were found there a difference in the conversion rate of 0.25%.
Mini Boone is located right at Fermilab, just 500 m from a neutrino source. In the new results now seem to Mini Boone confirmed the observations of Los Alamos. The chance that a background signal has the signal is simulated, but still in good 3%.
