Search

The NA62 experiment at CERN aims at measuring the ultra-rare decay with a 10% accuracy; the main background is which is suppressed by means of kinematical cuts and by the different stopping power of and . A further suppression must be provided by a RICH detector in a momentum range between 15 and 35 GeV/c. In this paper a RICH filled with Neon at atmospheric pressure contained in a 17 m long, 3 m wide vessel and in which the Cherenkov light is readout by 2000 single-anode photomultipliers, will be described. The results of a test beam performed with a prototype will be presented. [Copyright &y& Elsevier]

Recent results on CP violation on kaons by the CERN NA48 experiment will be discussed. A preliminary measurement of the charge asymmetry in KL → π±e∓ν has been made: δLe = (3.317±0.070stat±0.072syst) × 10−3. A search for KS → 3π0 decays has been performed with a preliminary estimation of the real and imaginary part of the η000 parameter: Re(η000) = (−2.6±1.0stat±0.5syst) × 10−2 and Im(ηn000) = (−3.4±1.0tstat±1.1syst) × 10−2. The angular asymmetry in KL → π+π−e+e− has been measured to be AL = (14.2 ± 3.0stat ± 1.9syst)%, while no asymmetry has been observed in K → π+π−e+e−: AS = (0.5 ± 4.0stat ± 1.6syst)%. Finally, the direct CP violation in KnS,L → 2π has been clearly settled, with tRe(ε′/ε) = (14.7 ± 2.2) × 10−4. [Copyright &y& Elsevier]