Evidence for Neutrino Disappearance

decowski writes "Results from the first six months of experiments at KamLAND, an underground neutrino detector in central Japan, show that anti-neutrinos emanating from nearby nuclear reactors are "disappearing," which indicates they have mass and can oscillate or change from one type to another. As anti-neutrinos are the anti-matter counterpart to neutrinos, these results provide independent confirmation of earlier studies involving solar neutrinos and show that the Standard Model of Particle Physics, which has successfully explained fundamental physics since the 1970's, is in need of updating. The results also point the way to the first direct measurements of the total radioactivity of the earth."

Comments

Re:Minor quibble, or addendum

[Peter T Ermit]

IIRC, the publication of the g-2 results was in 2001 and 2002. There's probably a third release coming, where they release the mu-plus results, too.

When it comes down to it, the g-2 stuff is just a three-sigma deviation from the standard model -- interesting, and better than most other three-sigma results out there, but not definitive. The neutrino results, first at Super-K, SNO, and K2K, and now at KamLAND, are pretty much definitive.

Besides, the g-2 result and the neutrino results each require different modifications to the standard model; the latter requires supersymmetry or some extension of the model, whereas the former requires the assumption of mass in existing particles.