Investigation of Long Drift Chambers for a Nucleon Decay Detector

We have built a successful prototype of a long drift chamber to be used for a nucleon decay experiment. In order to minimize the attenuation of drifting electrons, it was necessary to produce the drift electric field with a continuous electrode, realized with a film of resistive ink, which prevented charging of dielectric surfaces andeliminated outside effects. A focussing electric field shape was used to reduce loss of electrons by diffusion into the walls of the chamber.