Author :
Artuso, M. ; Azfar, F. ; Efimov, A. ; Kopp, S. ; Mountain, R. ; Schuh, S. ; Skwarnicki, T. ; Stone, S. ; Viehhauser, G. ; Anderson, S. ; Smith, A. ; Kubota, Y. ; Lipeles, E. ; Coan, T. ; Staeck, J. ; Fadeyev, V. ; Volobouev, I. ; Ye, J.
Abstract :
The CLEO collaboration is preparing a major upgrade of its present detector including a RICH detector for particle identification. This subdetector system follows the `proximity focussing´ design and uses LiF crystal radiators and MWPCs filled with a CH4/TEA gas mixture as photon detector. Part of the radiator crystals will have the new `sawtooth´ geometry. We have constructed two of the 30 detector modules and tested these together with the first planar and `sawtooth´ radiator crystals in a muon halo beam at Fermilab. For the measurement of the Cherenkov angle we obtain a single photon measurement error of 13.5 mrad for the conventional planar radiator. With 14 detected photons we find a resolution per track of 4.5 mrad. In the first measurement ever of a `sawtooth´ radiator we achieve a resolution of 11.8 mrad for single photons and 4.8 mrad per track for 12.3 detected photons with a reduced geometric acceptance. These results fulfil CLEO III requirements
Keywords :
Cherenkov counters; gamma-ray detection; muon detection; CLEO III; LiF; RICH detector; muon halo beam; particle identification; proximity focussing; sawtooth radiator crystals; single photon measurement; Collaboration; Crystalline materials; Detectors; Optical distortion; Optical reflection; Optical refraction; Optical surface waves; Optoelectronic and photonic sensors; Photonic crystals; Testing;
