2024-10-06 06:36:04
An international team of scientists, including researchers from the University of Birmingham and the University of Florence, have observed for the first time the ultra-rare decay of a charged kaon into a pion and a neutrino-antineutrino pair (K+ → π+νṽ). The results of the study, a press release of which was published on the Phys.org website, were confirmed at a significance level of five sigma and indicate the possibility of the existence of New Physics, Day.Az reports.
This decay is predicted by the Standard Model, which explains the interaction of elementary particles. However, its probability is extremely low: only one kaon in ten billion decays in this way. A new measurement of this process was made possible by the NA62 experiment, which was specially designed to observe decays of this type.
The experiment is carried out at CERN using a high-intensity proton beam that collides with a stationary target, producing a beam of particles, including kaons. The NA62 detector tracks kaon decay products with the exception of neutrinos, which are detected by missing energy. An important element of the experiment is the precise measurement of each particle and the suppression of background signals.
New data obtained in 2021-2022, combined with previously published results for 2016-2018, improved the accuracy of observations. Modernization of equipment and analysis methods made it possible to increase beam intensity by 30 percent and speed up signal collection by 50 percent.
The collected data showed that the proportion of kaons decaying into pions and neutrinos is approximately 13 per 100 billion. This figure matches the predictions of the Standard Model, but is about 50 percent higher, which may indicate the presence of new particles. A significance level of five sigma indicates a clear difference from statistical chance.
At the moment, the experiment is ongoing, and scientists plan to collect more data to test the hypothesis of new physics beyond the Standard Model. In the next few years, researchers hope to confirm or rule out the possibility of new particles that influence this process.