LHCb RICH Detectors

The LHCb experiment will perform high precision studies of CP violation and other rare phenomena in the $B$ meson sector. Particle identification will be essential to enhance the signal to background ratio in the selection of $B$ decay channels and to provide an efficient kaon tag. LHCb will use two RICH gaseous C$_4$F$_{10}$ radiators, and the other covering up to 100 GeV/c using gaseous CF$_4$. Hybrid Photon Detectors (HPDs) have been developed to detect Cherenkov light in the wavelength range 200-600 nm. The engineering design of the upstream RICH 1 detector is very well advances and the assembly of the downstream RICH 2 is almost complete.