Operation of a Fast-RICH Prototype with VLSI readout electronics

Abstract We discuss the first test results, obtained with cosmic rays, of a full-scale Fast-RICH Prototype with proximity-focused 10 mm thick LiF (CaF 2 ) solid radiators, TEA as photosensor in CH 4 , and readout of 12 × 10 3 cathode pads (5.334 × 6.604 mm 2 ) using dedicated VLSI electronics we have developed. The number of detected photoelectrons is 7.7 (6.9) for the CaF 2 (LiF) radiator, very near to the expected values 6.4 (7.5) from Monte Carlo simulations. The single-photon Cherenkov angle resolution σ θ = 19.1 (15.2) mrad for the CaF 2 (LiF) radiator, to be compared with 19.3 (13.2) mrad predicted by the Monte Carlo calculations. These first results have shown that the Fast-RICH Prototype works well and that the technique is well-suited for the next generation of high luminosity e + e − or hadron colliders.