N. Akopov

The HERMES dual-radiator ring imaging Cherenkov detector

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 15 GeV , which is essential to these studies. The instrument uses two radiators, C 4 F 10 , 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.

Hadron formation in deep-inelastic positron scattering from {sup 14}N and {sub 2}H.

Abstract. The influence of the nuclear medium on the production of charged hadrons in semi-inclusive deep-inelastic scattering has been studied by the HERMES experiment at DESY using a 27.5 GeV positron beam. The differential multiplicity of charged hadrons and identified charged pions from nitrogen relative to that from deuterium has been measured as a function of the virtual photon energy

The OLYMPUS experiment

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Application of the two-scale model to the HERMES data on nuclear attenuation

and the fraction z of this energy transferred to the hadron. There are observed substantial reductions of the multiplicity ratio

Performance of F101 Radiation Resistant Lead Glass Shower Counters.

R_M^{h}

Simple parameterization of nuclear attenuation data

at low

Possible influence of the two string events on the hadron formation in a nuclear environment

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Nuclear attenuation of high energy two-hadron system in the string model

and at high z, both of which are well described by a gluon-bremsstrahlung model of hadronization. A significant difference of the

Backward production of mesons associated with Delta++ (1232) in pi+ p interactions at 20-GeV/c

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The time-of-flight technique for the HERMES experiment

-dependence of