At a seminar at CERN, the NA62 collaboration announced the confirmed observation of the ultra-rare decay of a positively charged kaon (K+) into a positively charged pion (π+) and a neutrino–antineutrino pair, marked by a statistical significance of five standard deviations.

This decay, K+→π+νν, is one of the rarest processes in particle physics, predicted to occur in fewer than one in 10 billion kaons according to the Standard Model.

NA62’s measurement indicates a decay fraction of 13.0 +3.3/-2.9 × 10^-11, about 50% larger than predicted, though still compatible within the uncertainty range.

This discovery, part of a decade-long project, offers a promising avenue for exploring new physics beyond the Standard Model, CERN has reported.

Enhanced detector capabilities and data analysis techniques contributed to this breakthrough, which could lead to further investigations in the coming years.

Written by B.C. Begley