Studying the characteristics of multiwire proportional chambers with cathode data readont

The characteristics of a multiwire proportional chambers with cathode data readout in which cathode wires are joined into groups (strips) by 6 wires in each, that makes it possible to reduce an electronic part of the system are studied. The anode plane of the chamber, consisting of gold-coated tungsten wires 20 μm in-diameter fixed with the 2 mm pitch, is placed between two cathode planes. The distance between the anode and cathodes constitutes 4.8 mm. Cathodes are made of the Ni-Cr alloy wires 50 μm in diameter placed with the pitch of 1 mm. The direction of cathode wires is perpendicular to the anode wire direction. The accuracy of the winding pitch both for anodes and cathodes constitutes +-5 μm. Displacement of the cathode planes in respect to each other and the value of the distance between the anode and cathode are approximately +-5 μm. Error in parallelism of the cathode plane and deviation of anode wires from the normal to cathode ones constitute +-0.2 mrad. The working area of the chamber is 54x70 mm. The chamber is blown-through by the ''magic'' gas mixture including 65% argon +30% isobutane +5% methylal +0.4% freon. The rate of blowing is 4.5 l/h. The analysis of the data obtained shows that the accuracy of charged particle coordinate determination in the chambers considered constitutes 37 μm, the time resolution is 16 ns. The conclusion is made that initiation of self-quenching streamer discharge in the chamber leads to the device spatial resolution worsening