NA62 present status

NA62 is a fixed-target experiment located in the CERN experimental North Area. The beam is provided by SPS. During the first phase (2007 → 2010) the collaboration measured the ratio RK = BR(K → eν)/BR(K → μν). This measurement is sensitive to Standard Model (SM) deviations; in particular it can test lepton universality. During the second phase, the collaboration aims to measure BR(K+ → π+ν¯ν). Due to the sensitivity of this BR to new physics, this decay has a strategic role in the search for physics beyond the SM. The hadronic contribution to the uncertainty is small and the SM prediction is precise: (8.5 ± 0.7)10−11. The apparatus is under construction and the first run is expected for spring 2013. The detector status, prototype tests, and signal sensitivity compared with background rejection will be discussed