The COMPASS RICH-1 fast photon detection system

Towards THGEM UV-photon detectors for RICH: on single-photon detection efficiency in Ne/CH4and Ne/CF4

“…The efficiency of transferring avalanche electrons from stage to stage, does not affect ε effph . 2 Optimal THGEM: t = 0.4 mm , d = 0.3 mm, a = 1 mm; h = 0.01 mm, 3 Value for 1.5 kV/cm photocathode electric field 4 Values for 2kV/cm photocathode electric field Note, that the absolute efficiency of detecting single photons ε photon , e.g. in RICH, depends both on the detector's effective photon detection efficiency ε effph and on the achievable gain (detected pulses above threshold (fp th )).…”

“…The development of advanced imaging Cherenkov detectors is a subject of intensive R&D; examples are novel UV-photon detectors for RICH in CERN-Super LHC-ALICE [1] and CERN-COMPASS [2]. The requirements imposed by these experiments include high sensitivity to single photons, stable operation under intense ionizing-radiation background and the possibility of covering large detection area at low production cost.…”

Cherenkov light imaging—Fundamentals and recent developments

“…The fourth generation detectors, like BaBar-DIRC [6,37], CLEO-III [38][39][40], COMPASS [41][42][43], are all well understood devices, do not present too much operational problems, and are part of the physics analysis of the experiment.…”

Status and perspectives of vacuum-based photon detectors for single photon detection

“…The upgrade of the COMPASS RICH-1 detector central region required photon detectors and associated electronics allowing trigger rates in the 100 kHz range and beam rates of 100 MHz, corresponding to single channel counting rates of up to several MHz [4][5][6]. These requirements are fulfilled by MaPMTs.…”

“…Fused-silica field lens (left) and concentrator lens (centre) used to increase the active area coverage of the MaPMT (right) in COMPASS RICH-1 (from Refs [4][5][6]…”