A low-density, cylindrical MWPC with simultaneous anode and cathode read-out for use in a magnetic detector

Abstract We describe the construction and performance of a cylindrical proportional chamber with anode and cathode detection permitting simultaneous axial and azimuthal localization without ambiguity. The anode wires are strung parallel to the chamber axis, while the inner and outer cathode wires form helices inclined at −45° and +45°, respectively. The average chamber thickness is 10 −3 radiation lengths. At 100% efficiency the anode and cathode plateau widths are 600 and 300 V, respectively.