Performance of the RICH Detectors of LHCb

Hadron identification, in particular the ability to distinguish charged kaons and pions, is crucial to many of LHCb core physics analyses. LHCb Ring Imaging CHerenkov (RICH) detector fulfils this role by providing charged particle identificationin the momentum range between1and 100 GeV/c. The calibration and monitoring of the RICH detectors is achieved using samples of D ∗, K S 0 , Λ and φ events, which are plentiful in the data and can be cleanly isolated through their decay kinematics. The particle identification performance of the LHCb RICH detectors, measured in data taken during the 2010 and 2011 LHC runs, will be presented along with the strategy for aligning and calibrating the detector. Finally this performance will be placed in context by highlighting the impact of the RICH performance on some of LHCb benchmark analyses.