CHICAGO (Kyodo) -- Through experiments in Japan, a team of researchers has detected the possibility that a subatomic particle, called neutrinos, and its corresponding antimatter element may be slightly asymmetric in nature, a finding that could shed light on the birth of the universe.
The team, led by Japanese researchers, presented their discovery from a probe using the Super-Kamiokande neutrino observatory in central Japan at an academic conference in Chicago on Saturday.
It has been theorized that subatomic particles such as electrons and protons have corresponding "antimatter" particles and that matter and antimatter annihilate one another and produce energy if they collide.
It remains a mystery why today virtually only matter exists in the universe, although equal numbers of matter and antimatter were thought to have been produced when the universe came into being after the Big Bang.
The latest study may provide a clue to understanding why, one of the greatest mysteries of the universe.
The scientists, who include researchers from Japan's High Energy Accelerator Research Organization, generated neutrinos, one of the elementary particles that exist in the universe, and its corresponding antimatter, antineutrinos, at the Japan Proton Accelerator Research Complex, or J-PARC, northeast of Tokyo.
They then discharged 100 trillion neutrinos and as many antineutrinos per second from the J-PARC complex toward the Super Kamiokande facility some 295 kilometers away.
Neutrinos travel across the universe by passing through intervening matter and changing into one of its three forms -- electron, muon and tauon.
At Super Kamiokande, the researchers examined particles that transformed from muon neutrinos to electron neutrinos -- and found there were 32 such neutrinos but only four such antineutrinos.
This asymmetry is believed to explain why more matter than antimatter remains in the universe.
More verification is required as the difference was not detected in all the cases examined, they said.
"We were able to reach the first starting point. We hope to gather more data to enhance the credibility" of our finding, said Tsuyoshi Nakaya, a Kyoto University professor who led the experiment.
The team, led by Japanese researchers, presented their discovery from a probe using the Super-Kamiokande neutrino observatory in central Japan at an academic conference in Chicago on Saturday.
It has been theorized that subatomic particles such as electrons and protons have corresponding "antimatter" particles and that matter and antimatter annihilate one another and produce energy if they collide.
It remains a mystery why today virtually only matter exists in the universe, although equal numbers of matter and antimatter were thought to have been produced when the universe came into being after the Big Bang.
The latest study may provide a clue to understanding why, one of the greatest mysteries of the universe.
The scientists, who include researchers from Japan's High Energy Accelerator Research Organization, generated neutrinos, one of the elementary particles that exist in the universe, and its corresponding antimatter, antineutrinos, at the Japan Proton Accelerator Research Complex, or J-PARC, northeast of Tokyo.
They then discharged 100 trillion neutrinos and as many antineutrinos per second from the J-PARC complex toward the Super Kamiokande facility some 295 kilometers away.
Neutrinos travel across the universe by passing through intervening matter and changing into one of its three forms -- electron, muon and tauon.
At Super Kamiokande, the researchers examined particles that transformed from muon neutrinos to electron neutrinos -- and found there were 32 such neutrinos but only four such antineutrinos.
This asymmetry is believed to explain why more matter than antimatter remains in the universe.
More verification is required as the difference was not detected in all the cases examined, they said.
"We were able to reach the first starting point. We hope to gather more data to enhance the credibility" of our finding, said Tsuyoshi Nakaya, a Kyoto University professor who led the experiment.