Development of aerogel Cherenkov counters with wavelength shifters and phototubes

The paper deals with the development of Cherenkov counters based on Aerogel , wavelength SHIfters and PHototubes (ASHIPH). Microchannel plate photomult ipliers with multialkali photocathodes are used. Data on the PMT multiplica tion gain in the magnetic held and noise are presented. The main parameters of the wavelength shifters, aerogel SAN-96, and the PTFE reflector are mea sured. The project of the ASHIPH system is developed for the KEDR detector. The counters will operate in a 1.8 T magnetic field and will separate pi- and K-mesons in the momentum region of 0.6 -1.5 GeV/c. Compared to the opti on of the direct light collection on the photomultiplier, this method offer s a possibility to diminish the number of PMTs essentially. The possibility to increase light collection in the ASHIPH detector using a combination of 'blue' and 'green' shifters is discussed. (C) 1998 Elsevier Science B.V. A ll rights reserved.