The SELEX Phototube RICH Detector
  In this article, construction, operation, and performance of the RICH detector of Fermilab experiment 781 (SELEX) are described. The detector utilizes a matrix of 2848 phototubes for the photocathode to detect Cherenkov photons generated in a 10m Neon radiator. For the central region an N0 of 104/cm, corresponding to 13.6 hits on a beta=1 ring, was obtained. The ring radius resolution measured is 1.6%. 
J. Engelfried (1), I. Filimonov (2), J. Kilmer (1), A. Kozhevnikov   (3), V. Kubarovsky (3), V. Molchanov (3), A. Nemitkin (...