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Thesis (Masters Diploma (Technology)--Cape Technikon, Cape Town,1992 / This research project involved the design, development and manufacture of a krypton gas target system for the production of the radioisotope Rubidium-81 at the National Accelerator Centre (NAC). The newly designed system had to be linked to the existing production facilities, which set certain restraints and fIxed parameters to the design approach. The highl'ressure krypton-filled gas target was designed to link up to the existing transport system which is used for the transportation of all targets to and from the target bombardment station and· the hot-cells where processing takes place. Radiation resistant materials had to be selected for the target, as it would be exposed to high radiation doses during bombardment in the target bombardment station. Target cooling aspects also had to be taken into consideration due to the heat generated during bombardment. A cryopump system for transferring the krypton gas from a gas storage reservoir to the gas target and back during loading and unloading was developed. A further development was a system which would retrieve the formed radioisotopes in a water suspension after bombardment. This demanded the design of a set of spray nozzles which were mounted inside the gas target chamber, a suitable water circulating pump and ruters to trap the suspended radioisotopes. Due to the high radiation levels] which are, of course, dangerous to operating personnel, the whole system was constructed inside a hot-cell, and thus required the design of a fully remote control system together with gas monitoring and safety components. The processing system itself required many switching and monitoring opera.tions which ha.ve to be carried out accurately and sequentially and this further demanded making use of a microcomputer control system. Material strengths, manufacturing methods, performance and selection of the VarIOus components in the system were investigated, as well as the respective routine maintenance and repair aspects.

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Le but poursuivi dans cette thèse est la mesure du déplacement de la fréquence hyperfine du Rubidium 87 plongé dans l'azote moléculaire (N₂) à différentes densités, autour d'une température T₀ de 60 °C. Les résultats sont représentés par un développement en série, jusqu’au second degré en (T-T₀).Nous donnons la valeur des coefficients de déplacement de fréquence, définis comme les coefficients de ce développement normalisés à la densité de N₂. Nous avons observé une non linéarité du déplacement de fréquence en fonction de la densité de N₂, que nous interprétons comme découlant d'une erreur systématique sur la densité. Cette interprétation s'appuie sur une évaluation théorique de la non linéarité, et nous conduit à donner au coefficient de pression la valeur de la pente à l'origine de la courbe du déplacement de fréquence en fonction de la densité… / Québec Université Laval, Bibliothèque 2019

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Dual-comb spectroscopy (DCS) has widespread applications. It has become a more prominent spectroscopic tool because it has broad spectral coverage with high frequency resolution. We demonstrate the broadband and high resolution of DCS to probe transient events, showing the rst use of DCS of laser-induced plasmas (LIPs). Our measurements span absorption features 7 THz wide, simultaneously detecting Rb D2, K D1 and D2 absorption lines with the ability to resolve the isotope ratios in the Rb D2 line. This technique is more broadband and faster than tunable laser absorption spectroscopy because it eliminates the requirement to scan across transitions. Additionally, DCS makes higher resolution measurements than laser-induced break- down spectroscopy. Our ultimate goal is to use DCS as a technique to ascertain the chemical composition of unknown samples. Our rst demonstration of this technique illustrates that DCS makes broadband, high-resolution measurements with the ability to measure isotope ratios, which is necessary for determining sample composition.