The NA62 experimental team at the European Organization for Nuclear Research (CERN) has successfully observed for the first time in the laboratory the decay of charged K mesons into charged π mesons and neutrino pairs, with a confidence level of 5 sigma (99.9999%) required to claim a "new discovery". This rare particle decay process has the potential to uncover the mysteries of new physics beyond the Standard Model of particle physics. The relevant paper has been submitted to the European Symposium on Particle Physics held on the 24th. The goal of the NA62 experiment is to observe rare decay of K mesons with high precision. The Standard Model reveals the composition and interactions of matter, and predicts that the probability of K mesons undergoing this decay is less than one in ten billion. Therefore, observing this decay will become one of the most reliable ways to find new physical evidence. K mesons are produced by collisions between high-intensity proton beams provided by the CERN Super Proton Synchrotron and stationary targets. This collision produces a beam of secondary particles, causing nearly 1 billion particles to fly into the NA62 detector every second, of which about 6% are charged K-mesons. The detector accurately identified and measured K mesons and decay products other than neutrinos (neutrinos hardly interact with matter and exhibit "missing energy"). The observation results show that the probability of K mesons decaying into π mesons and neutrino pairs is about 13 in 100 billion. The research team pointed out that the latest observation results have become the rarest decay to date to reach the level of "discovery". The new observation results do not completely match the standard model, which may suggest the existence of some unknown new particles. However, more data is needed to confirm this speculation. At present, the NA62 experiment is collecting new data, which is expected to confirm or rule out the existence of new physics in this decay in the future. The new results are based on the NA62 experiment datasets from 2021 to 2022 and from 2016 to 2018. The dataset for 2021-2022 was collected after a series of upgrades to the NA62 device, with hardware upgrades and fine analysis techniques working together to increase the speed of signal collection by 50%. (New Society)