Drift chamber readout with 1 Gsample/s full signal digitization

This paper describes the performances of a large volume drift chamber with complete digitization of the output pulses. The electronics used in this test include wide-band (700 MHz) amplifiers and fast (1 Gsample/s) digitizers. The gas mixture selected for drift chamber operation (80% He–20% CH4) and the signal processing mentioned above allow the measurement of the primary ionization clusters. The improvement in the (wire) impact parameter evaluation of the primary particle is sizeable.