Bidimensional drift chamber

A drift chamber is described in which one coordinate is measured by time drift. A signal electrode sense wire on which an avalanche pulse appears determines the second coordinate. The spatial resolution (fwhm) for one coordinate changes from 0.23 mm to 0.72 mm for drift paths of 1 and 10 cm respectively and for the second coordinate it equals 4 mm for 3 mm distance between the sense wires. With a gas mixture of Ar + 10% CO2 the efficiency for relativistic particles exceeded 99%. (Auth.)