The NA62 Experiment at CERN: Prospects for the K+ ->pi+ nu nubar Measurement

The NA62 Experiment aims to measure the branching ratio of the ultra-rare K+ !p+n ¯ n decay with 10% precision, collecting 100 events with the SM branching fraction in 3 years of data taking. The NA62 experimental strategy and the detector layout are describe

SEARCH FOR AN INVISIBLE VECTOR BOSON FROM π0\pi^{0} DECAYS AT NA62

The high-intensity setup, trigger system flexibility and detector performance make the NA62 experiment at CERN particularly suitable to perform direct searches for long-lived hidden-sector particles, such as dark photons, dark scalars, axion-like particles, and heavy neutral leptons, using kaon and pion decays as well as operating the experiment in dump mode. Results from NA62 will be presented on a search for $π^0$ decays to one photon and an invisible massive dark photon. From about 400 M $π^0$ decays, no signal is observed beyond the expected fluctuation of the background and limits are set in the plane of the dark photon coupling to ordinary photon versus the dark photon mass. The analysis has been also interpreted in terms of the branching ratio for the electroweak decay $π^0 → γνν^¯$