Development of New Neutron Diagnostics for the PF1000 Plasma Focus Installation

Abstract

Summary form only given. The problem of determining with adequate accuracy the neutron yield of the PF1000 megajoule plasma focus device was addressed by introducing a new diagnostics technique based on the superheated fluid detectors, SHFD ("bubble detectors"). The use of the SHFD's, which are insensitive to thermal neutrons and electromagnetic radiation, allowed for the application of a new technique for the calibration of the existing activation detectors. The spatial characteristics of the neutron source on the PF1000 machine is of particular interest for using this device as a fast neutron source. In this respect, new techniques for the investigation of the neutron source with spatial and time resolution have been developed. In one experimental set-up two fast (fibre) scintillator-photomultiplier detectors have been used to investigate the axial distribution of the neutron emission with space and time resolution. Time-integrated information about the axial distribution of the neutron source was obtained by means of SHFD's placed inside two long paraffin collimators. The spatial and temporal characteristics of the PF1000 neutron source will be investigated in the near future by means of a new, advanced neutron pinhole camera diagnostics system which is at the moment in the design stage.