Scientists noticed some neutrinos had "shape shifted" after being beamed almost 200 miles away.
The researchers have made the very first definitive observation of "muon neutrino to electron neutrino transformation."
The team first noticed the neutrino oscillation process in 2011, but were unable to establish their finding until now, a European Physical Society press release reported.
During the process the neutron essentially shape shifts from one "flavor" to another, LiveScience reported.
Flavors are "different versions of the same type of particle"
Neutrinos come in three flavors "electron, muon and tau." The scientists observed muon particles turning into electron neutrinos.
Researchers with the T2K neutrino experiment in Japan streamed muon neutrinos to the Super-Kamiokande neutrino detector 183 miles away.
Researchers were expecting to detect about 6.4 electrons in the beam, but found 22.5. This suggested a number of the muon neutrinos had "shape shifted" into electron particles.
The study may lead to new insight into the nature of matter.
"Our findings now open the possibility to study this process for neutrinos and their antimatter partners, the anti-neutrinos," Alfons Weberm a physicist at the U.K. Science and Technology Facilities Council and the University of Oxford, said in a statement. "A difference in the rate of electron or anti-electron neutrino being produced may lead us to understand why there is so much more matter than antimatter in the universe. The neutrino may be the very reason we are here."
The next phase of the project may not produce new findings for up to 10 years.
"We have seen a new way for neutrinos to change, and now we have to find out if neutrinos and anti-neutrinos do it the same way," T2K team member Dave Wark of the Science and Technology Facilities Council said in a statement. "If they don't, it may be a clue to help solve the mystery of where the matter in the universe came from in the first place. Surely answering that is worth a couple of decades of work!"
Super Kamiokande is the "world's largest underground neutrino detector," according to T2K. It observes neutrinos, which are produced by the "collisions between cosmic rays and molecules in the Earth's upper atmosphere."
The detector also looks for proton decays, which have still never been detected.
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