The RICH detectors for the upgraded LHCb experiment

The LHCb experiment is designed to operate at an LHC luminosity of 2×1032 cm−2 s−1, or typically one collision per bunch crossing. After about five years it will have recorded a data sample of 10 fb−1. At this time LHCb plans an upgrade to operate the detector at a significantly increased luminosity that will greatly extend its potential for discovery and study of new phenomena. Studies performed to optimise the design of the LHCb upgrade are presented. The RICH detector will require new photon detectors as the current HPDs have encapsulated electronics which only support a readout rate of up to 1 MHz. Multi-anode and flat-panel photo multiplier tubes (PMTs) are evaluated as photon detector candidates and their properties including pulse height, shape and cross-talk are measured. The particle identification performance is studied as a function of luminosities ranging up to ten times the design as foreseen for the LHCb upgrade. Finally, the performance of flavour tagging using kaons, which strongly relies on RICH particle identification is also presented.