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The kaon physics programme, long heralded as a cutting-edge frontier by the European Strategy for Particle Physics, continues to stand at the intersection of discovery and innovation in high-energy physics (HEP). With its unparalleled capacity to explore new physics at the multi-TeV scale, kaon research is poised to unveil phenomena that could reshape our understanding of the Universe. This document highlights the compelling physics case, with emphasis on exciting new opportunities for advancing kaon physics not only in Europe but also on a global stage. As an important player in the future of HEP, the kaon programme promises to drivemore » transformative breakthroughs, inviting exploration at the forefront of scientific discovery.« less

A measurement of the $${K}^{+}\to {\pi}^{+}\nu \overline{\nu}$$ decay by the NA62 experiment at the CERN SPS is presented, using data collected in 2021 and 2022. This dataset was recorded, after modifications to the beamline and detectors, at a higher instantaneous beam intensity with respect to the 2016–2018 data taking. Combining NA62 data collected in 2016–2022, a measurement $$\mathcal{B} ({K}^{+}\to {\pi}^{+}\nu \overline{\nu}) = \large{(}13.0^{+3.3}_{-3.0}\large{)}$$ x $$10^{-11}$$ of is reported. With 51 signal candidates observed and an expected background of $$18^{+3}_{-2}$$ events, $$\mathcal{B} ({K}^{+}\to {\pi}^{+}\nu \overline{\nu})$$ becomes the smallest branching ratio measured with a signal significance above 5σ.