Second Coordinate Readout in Drift Chambers by Timing of the Electromagnetic Wave Propagating along the Anode Wire

The feasibility of using an anode wire and surrounding electrodes in drift chambers as a transmission line for second coordinate readout has been studied. The method is based on propagation of the electromagnetic wave along the anode wire. The position of the avalanche along the anode wire is determined by measurement, in an optimized electronic readout system, of the time difference between the arrivals of the signal to the ends of the wire. The resolution obtained on long wires (~ 2 meters) is about 2 cm FWHM for minimum ionizing particles at a gas gain of ¿ 105.