New Type of Neutrino Flip that Could Explain the Existence of Matter Confirmed

Scientists have firmly established a new type of transformation among neutrinos - the elusive, elementary particles so key to understanding the universe. In doing so, they may have placed researchers a large step forward in determining how the universe developed.

In 2011, the T2K collaboration, which includes physicists from the Albert Einstein Center for Fundamental Physics (AEC) of the University of Bern, announced the first indication of muon neutrino to electron neutrino transformation.

Now, just two years later, this transformation is firmly established with a significance of better than 1 in 16 trillion, which, the researchers explain, is as likely as getting six correct digits in the Swiss Lottery twice in a row.

In the T2K experiment, a muon neutrino beam is produced in the Japan Proton Accelerator Research Complex, called J-PARC, and aimed at the gigantic Super-Kamiokande underground detector 295 kilometers (184 miles) away.

A subsequent analysis of the data from the latter reveals more electron neutrinos in the beam from J-PARC than at the start of the journey, showing that a transformation must have taken place.

According to the researchers, this study represents the first time electron neutrinos were unequivocally observed in a beam of muon neutrinos.

In order to perform such a measurement, one needs to precisely study the properties of the neutrino beam at the production point, including the energy of the neutrinos and the number of electron neutrinos before the transformation, among other things.

For this reason, a detector complex in Tokai was built and is operated. There, researchers from the University of Bern installed and calibrated a huge magnet that encloses a set of devices at 280 meters (919 feet) from the production point is used to identify the particles and  .

Knowing that muon neutrinos can flip, or oscillate, is key to understanding how the universe came to be what it is today since it indicates that neutrinos and their anti-particle version might behavie differently. And if this is the case, it's possible that this is the reason there is so much more mater in the universe than antimatter.

"The fact that we have matter in the universe means there have to be laws of physics that aren't in our Standard Model, and neutrinos are one place they might be," Dave Wark, of the UK's Science and Technology Facilities Council and Oxford University, told BBC News.