T2K Results Restrict Possible Values of Neutrino CP Phase

Published in Nature, the results are a major step forward in the study of difference between matter and antimatter

The T2K Collaboration has published new results showing the strongest constraint yet on the parameter that governs the breaking of the symmetry between matter and antimatter in neutrino oscillations.

Intérieur du détecteur Super Kamiokande, construit sous une montagne au Japon. Photo de 2006.
Image: Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo

Professor Federico Sanchez (University of Geneva), spokesperson of the T2K Experiment, comments on the T2K publication about the indication of the matter-antimatter symmetry violation in neutrinos: "These results indicate that CP violation in neutrino mixing may be large, and T2K looks forward to continued operation with the prospect of establishing evidence for CP violation in neutrino oscillations."

The results show the strongest constraint yet on the parameter governing CP violation in neutrino oscillations, one of the few parameters governing fundamental particle interactions that has not yet been precisely measured.

Prof. Sanchez underlines the full team effort to obtain this results: "These exciting results are thanks to the hard work of hundreds of T2K collaborators involved in the construction, data collection and data analysis for T2K over the past two decades."

The full press release from the experiment can be found in the T2k website and in the Nature article.

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  • Elementary particles
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