The NA62 RICH detector

The NA62 experiment at CERN aims to measure the ultra-rare decay K+→π+νν¯ with a 10% accuracy; the main background, K+→μ+νK+→μ+ν, is suppressed using kinematical cuts and exploiting the different stopping power of π+π+ and μ+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.