A HIGH-RESOLUTION DETECTOR BASED ON LIQUID-CORE SCINTILLATING FIBERS WITH READOUT VIA AN ELECTRON-BOMBARDED CHARGE-COUPLED-DEVICE

This paper is a presentation of results from tests in a 5 GeV/c hadron beam of detectors based on liquid-core scintillating fibres, each fibre consisting of a glass capillary filled with organic liquid scintillator. Fibre readout was performed via an Electron-Bombarded Charge-Coupled Device (EBCCD) image tube, a novel instrument that combines the functions of a high-gain, gated image intensifier and a Charge-Coupled Device. Using 1-methylnaphthalene doped with 3 g/l of R45 as liquid scintillator, the attenuation lengths obtained for light propagation over distances greater than 16 cm were 1.5 m in fibres of 20 mu m core and 1.0 m in fibres of 16 mu m core. For particles that crossed the fibres of 20 mu m core at distances of similar to 1.8 cm and similar to 95 cm from the fibres' readout ends, the recorded hit densities were 5.3 mm(-1) and 2.5 mm(-1) respectively. Using 1-methylnaphthalene doped with 3.6 g/l of R39 as liquid scintillator and fibres of 75 mu m core, the hit density obtained for particles that crossed the fibres at a distance of similar to 1.8 cm from their readout ends was 8.5 mm(-1). With a specially designed bundle of tapered fibres, having core diameters that smoothly increase from 16 mu m to 75 mu m, a spatial precision of 6 mu m was measured.