The EXO collaboration, involving SLAC National Accelerator Laboratory, Stanford University, and many other partners, is looking for a never-before-observed process called neutrinoless double beta decay. In their case, this means watching for an isotope of xenon decaying into barium, giving off two electrons (the double beta decay), but without giving out any neutrinos. A beta decay process gives off one neutrino, so how could this even be possible? It only works if the neutrino is its own antiparticle, so that the two beta decays each have a neutrino which essentially cancel each other out, like matter and antimatter annihilating. And the possibility that process exists is the reason for the experiment.
If neutrinoless double beta decay is observed, it means the neutrino must be its own antiparticle, a key unknown in the study of neutrinos. If the neutrino is indeed its own antiparticle, it has all kinds of implications for the structure of the Standard Model and the relationships between the fundamental particles.
While many people would not be able to understand what's the big deal with the physics or what is being looked for, there is however, one important factor that should not be overlooked. These brilliant people are trying to look for extremely rare events. This is not particularly uncommon and is not unique to just this experiment. So just because the event is extremely rare and hard to find, it doesn't mean that it can't be found, or that there is no way to look for it.
The point I'm trying to make here is that many people who study "pseudoscience" phenomena often use the excuse that they are studying or trying to observe something that is difficult to detect and very rare. They often use such excuses as the reason why such paranormal phenomena cannot be reproduced on demand. I don't buy it for the very reason that in physics, it is not unheard of to look for such difficult and rare events. How many top quarks were found out of the gazillion collisions at the Tevatron that first time? This is not exactly "common"!
So it looks like we have another experiment to look forward to this year.