Search

NA62 is a new generation kaon experiment at the CERN SPS aiming at studying rare and forbidden decays. One of main challenges of the experiment is the suppression of background decay channels with branching ratios up to 10 orders of magnitude higher than the signal and with similar experimental signatures. To provide such suppression, a powerful particle identification (PID) is needed. A key element of PID in NA62 is the Ring Imaging Cherenkov (RICH) detector. The RICH has successfully operated during the 2016–2018 data taking periods, being essential in the measurement of the branching ratio of the K + → π + ν ν ̄ decay. The detector was also used for searches for lepton number violation in 3-track kaon decays. The results on the π / μ and π /e separation directly measured with the data for the aforementioned decays are presented. [ABSTRACT FROM AUTHOR]

The NA62 experiment aims to measure the B R (K + → π + ν ν ̄) with a 10% precision. One of the main backgrounds comes from the decay K + → μ + ν , therefore a highly powerful pion/muon separation is needed. The NA62 RICH, together with the calorimeter system, provides an accurate particle identification which has been essential to obtain the first results of the NA62 K + → π + ν ν ̄ analysis, based on 2016 data. Two different algorithms have been exploited which, used in combination, allowed to get a pion reconstruction and identification efficiency of 75%, with a muon suppression factor of about 500, in the momentum range 15–35 GeV/c. [ABSTRACT FROM AUTHOR]

The Ring Imaging Cherenkov detector of the NA62 experiment at CERN SPS was commissioned in 2014, but the optimal performance was achieved in 2016 after the precise mirror alignment with reconstructed tracks. The measurement and monitoring of basic performance parameters is discussed: ring radius resolution, ring centre resolution, single hit resolution and mean number of hits per ring. The performance is measured with 2016 data on the positron sample. Different contributions to the resolutions are calculated. [ABSTRACT FROM AUTHOR]