Modern particle physics shows interest on identification of high momentum particles, for which the ring imaging Cherenkov detectors (RICH) are excellent. The challange is to detect the single photons (emitted by the fast charged particles) with high efficiency and good spatial resolution. Gaseous detectors could be a good choice. The ThichGEM+CCC Photon Detector (TCPD) united features of the micropattern ThickGEM technology and the stability of the CCC wire chamber.
The incoming Cherenkov photon traverses the UV-transparent quartz window and the wire-grid-cathode, and is converted on the CsI plated top side side of the ThickGEM layer. The emitted electron goes towards the nearest hole and gets multiplied therein. The produced electron cloud can be detected on the CCC layer with high gain.
Beam tests at CERN PS showed stable operation even at total gain of 105. We have measured the operability of the TCPD with various gas mixtures, prooved the feature of MIP suppresstion, and in RICH mode its identification capability.
Author: Hamar Gergő