Performance of Foil Supported Electrode System and Plans for Improvement

In a previous communication the advantages and the performance of foil supported wires for counter arrays were described, and we hinted at rate limitations caused by voltage drop in the resistive foil. The non-uniform material properties which are never quite ruled out initially and often develop under irradiation, particle bombardment etc. - at least on the surface of organic foils, and the recent increase of stable gas-amplification make these limitations severe beyond our first expectation. This is a preliminary report on a changed approach: we use a good insulator for supporting the foil and eliminate the field distortion caused by surface charges through a self shielding geometry described below.