The NA62 RICH detector

The NA62 experiment at CERN aims to measure the ultra-rare decay K + → π + ν ν ¯ with a 10% accuracy; the main background, K + → μ + ν , is suppressed using kinematical cuts and exploiting the different stopping power of π + and μ + . A further 0.5% suppression will be provided by a RICH detector, in a momentum range between 15 and 35 GeV/c. In this paper the design parameters of a RICH detector that fulfills the NA62 experiment requirements will be described, as well as results from two different beam tests.