The HERMES dual-radiator ring imaging Cherenkov detector

Authors :: Akopov, N.
Aschenauer, E.C.
Bailey, K.
Bernreuther, S.
Bianchi, N.
Capitani, G.P.
Carter, P.
Cisbani, E.
De Leo, R.
De Sanctis, E.
De Schepper, D.
Djordjadze, V.
Filippone, B.W.
Frullani, S.
Garibaldi, F.
Hansen, J.-O.
Hommez, B.
Iodice, M.
Jackson, H.E.
Jung, P.
Source :: Nuclear Instruments & Methods in Physics Research Section A. Mar2002, Vol. 479 Issue 2/3, p511. 20p.
Publication Year :: 2002
Abstract: The construction and use of a dual radiator Ring Imaging Cherenkov (RICH) detector is described. This instrument was developed for the HERMES experiment at DESY which emphasises measurements of semi-inclusive deep-inelastic scattering. It provides particle identification for pions, kaons, and protons in the momentum range from 2 to <f>15 GeV</f>, which is essential to these studies. The instrument uses two radiators, <f>C4F10</f>, a heavy fluorocarbon gas, and a wall of silica aerogel tiles. The use of aerogel in a RICH detector has only recently become possible with the development of clear, large, homogeneous and hydrophobic aerogel. A lightweight mirror was constructed using a newly perfected technique to make resin-coated carbon-fiber surfaces of optical quality. The photon detector consists of 1934 photomultiplier tubes (PMT) for each detector half, held in a soft steel matrix to provide shielding against the residual field of the main spectrometer magnet. [Copyright &y& Elsevier]