New result on the search for the $K^+ \to \pi^+ \nu\bar\nu$ decay at the NA62 experiment at CERN

The ultra-rare $K^{+} \rightarrow \pi^{+}\nu\overline{\nu}$ decay benefits from a precisely predicted branching ratio in the SM$BR(K^{+} \rightarrow \pi^{+}\nu\overline{\nu}) = (8.4\pm 1.0)\times10^{-11}$, being almost free from theoretical uncertainties, andmost importantly from a very high sensitivity to a variety ofbeyond-the-standard-model scenarios, making it one of the bestcandidates to reveal indirect effects of new physics in the flavoursector. The NA62 experiment at the CERN SPS, designed to measurethe branching ratio of $K^{+} \rightarrow \pi^{+}\nu\overline{\nu}$with a decay-in-flight technique, collected data in 2016-2018. Newresults from the analysis of 2018 data, the largest data set so farcollected, will be presented. The result will represent the mostaccurate measurement so far achieved of this ultra-rare decay.