Medium-term stability of a Parallel Plate Avalanche Chamber with a bakelite electrode operated in high radiation flux

A gas detector made of three parallel electrodes ( bakelite electrode and two metallic mesh electrodes) and working in proportional mode allows monitoring of the gas gain under various intensities of X-rays over long period of time. The detector performance, when irradiated with an intense radiation flux, and possible effects of variation of the bakelite electrode conductivity on a medium-term stability of operation are reported. The results shown in this paper were obtained for detector filled with Argon/Isobutane gas mixture.