A TWIN GRID ION CHAMBER SUITABLE FOR FISSION CORRELATION EXPERIMENT

A twin grid ion chamber suitable for fission multi-parameter correlation experiment is designed and developed. Its behaviour is studied using a ~(252)Cf transfer fissile source on a stainless steel backing in the case when Ar (90％)+CH_4 (10％) mixture gas and pure CH_4 gas are selected as working gases. The ratio of the number of counts per channel at the peak of light fragment group to that at the minimum in the valley is about 2.8, this means that the energy resolution of detecting fission fragments is not worse than that of the barrier type detector. The cosθ of the fragment emission angle can be determined with a resolution in cosθ of 0. 03. Because of the constant fast rising leading edge, the cathode signals can be used as timing mark in the multi-parameter correlation experiments.