ABSTRACT
The paper concerns fast protons and neutrons from D-D fusion reactions in a Plasma-Focus-1000U facility. Measurements were performed with nuclear-track detectors arranged in "sandwiches" of an Al-foil and two PM-355 detectors separated by a polyethylene-plate. The Al-foil eliminated all primary deuterons, but was penetrable for fast fusion protons. The foil and first PM-355 detector were penetrable for fast neutrons, which were converted into recoil-protons in the polyethylene and recorded in the second PM-355 detector. The "sandwiches" were irradiated by discharges of comparable neutron-yields. Analyses of etched tracks and computer simulations of the fusion-products behavior in the detectors were performed.
ABSTRACT
The paper presents an improved version of a miniature mass-spectrometer of the Thomson-type, which has been adopted for ion analysis near the dense plasma region inside a vacuum chamber. Problems connected with the separation of ions from plasma streams are considered. Input diaphragms and pumping systems, needed to ensure good vacuum inside the analyzing region, are described. The application of the miniature Thomson-type analyzer is illustrated by ion parabolas recorded in plasma-focus facility and rod plasma injector experiment. A quantitative analysis of the recorded ion parabolas is presented. Factors influencing accuracy of the ion analysis are discussed and methods of the spectrometer calibration are described.
ABSTRACT
This paper concerns applications of solid state nuclear track detectors (SSNTDs) of the CR-39 type for measurements of ion streams emitted from the rod plasma injector (RPI). The main diagnostic tool was a Thomson-type mass spectrometer, To detect low energy ions use was made of an additional ion-acceleration system, which enabled the registration threshold to be lowered to about 25 keV. Simultaneously with the time-integrated measurements, time-resolved studies were performed of ion streams by means of Faraday-type collectors. It was shown that the investigated plasma-ion source generates also high energy ions, e.g. protons of energy of 2.6-3.7 MeV. For the analysis of the irradiated and etched CR-39 detectors use was made of a computerised system, which enabled determination of the dimensions of the registered tracks produced by low energy protons, deuterons and nitrogen ions. It has extended the known characteristics of the CR-39 detector.
