Very light tracking detector for jet target experiment in high energy physics

A description is given of a detector that constitutes the inner tracking part of the E760 experiment designed to study charmonium spectroscopy on the antiproton accumulator at FNAL. It is composed of a multiwire proportional chamber and a radial projection chamber on the same mechanical structure with cylindrical symmetry. Some special features are described which makes it possible to achieve field shaping and to minimize space-charge effects, multiple scattering, and photon conversion. The detector has been made as light as possible in order to minimize particle conversion in the sensitive zone ranging from 15 degrees to 50 degrees degrees in polar angle. A data display for a cosmic event is shown.<
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