Physics Beyond The Standard Model With Kaons At Na62

The NA62 experiment at CERN Super Proton Synchrotron was designed to measure BR(K+ -> pi+nu(nu) over bar) with an in-fight technique, never used before for this measurement. This decay is characterised by a very precise prediction in the Standard Model. Its branching ratio, which is expected to be less than 10(-10), is one of the best candidates to indicate indirect effects of new physics beyond SM at the highest mass scales. NA62 result on K+ -> pi(+)nu(nu) over bar from the full 2016 data set is described. Also a search for an invisible dark photon A' has been performed, exploiting the efficient photon-veto capability and high resolution tracking of the NA62. The signal stems from the chain K+ -> pi(+)pi(0) followed by pi(0) -> A'gamma. No significant statistical excess has been identified. Upper limits on the dark photon coupling to the ordinary photon as a function of the dark photon mass have been set, improving on the previous limits over the mass range 60 - 110 MeV/c(2).