Thesis (M. Sc.)--University of Alberta, 2009. / Title from PDF file main screen (viewed on Oct. 19, 2009). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science, Department of Electrical and Computer Engineering, University of Alberta. Includes bibliographical references.

Thesis (Ph. D.)--University of Florida, 1982. / Description based on print version record. Typescript. Vita. Includes bibliographical references (leaves 152-156).

Thesis (M.S.)--West Virginia University, 2005. / Title from document title page. Document formatted into pages; contains xii, 96 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 56-59).

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The new ion guide isotope separator, IGISOL--4, at JYFL, Jyvaskyla has been commissioned, and new spectroscopy and structural measurements are reported here. The first optical measurements of radioactive (101,107)Mo isotopes, with definite spin assignments, are presented. The measurements provide insight into the development of the structure and deformation around N=60 for molybdenum. A clear, exaggerated odd--even staggering in the mean--square charge radii up to N=60, followed by an immediate change in character, shows the chain to possess a far less smooth shape development than previously thought. The measurements of 107Mo confirm this isotope to mark the peak of the deformation in molybdenum and these results, achieved in the limits of fission fragment production, display the improved capabilities of the IGISOL--4 facility (these two isotopes were too challenging to be studied previously at IGISOL--3).The commissioning stages of the electrostatic ConeTrap are detailed, from the initial off--line investigations (in comparison to detailed simulations), to the first successfully stored and extracted radioactive ions. The detection of a hyperfine resonance has been achieved from (stable) hafnium ions stored and extracted from the trap prior to resonant excitation, with no observable ion energy perturbations induced by the trapping. The observation of a resonant optical pumping effect on yttrium ion survival is presented. Pumping of an ionic ensemble within the Cooler--Buncher is shown to lead to a change in ion survival, directly observed through a change in the measured ion rates. The ConeTrap was observed to enhance this effect upon further storage of pre--pumped ions. A new, bespoke data acquisition system for collinear laser spectroscopy is presented. The microcontroller based system provides time stamping of photon arrival, a multiple photon tracker for two photon gating and full software control over photon time gates. A novel approach for searching for weak hyperfine peaks is implemented in the system. This `photon multiplication method' provides greater statistics on resonance peaks, providing a greatly increased accuracy in peak centroid determination.

No description available.

Significant sub-systems were created and others enhanced providing a platform for an order of magnitude precision increase of the small 4He interval - 23P1→23P2 laser spectroscopy measurement, as well as other helium transitions. These measurements serve as tests of helium theory and quantum electro-dynamics in general. Many improvements to the original experiment are discussed and characterized. In particular, counting speed increased 10x, the signal level was doubled, a novel Doppler shift minimization technique was implemented, a control node re-architecture was realized along with many useful features, and the development environment was updated. An initial 28% precision improvement was achieved also providing a foundation for additional gain via a created smaller and more heavily windowed vacuum cavity and picomotor controls.

A collinear fast ion beam laser apparatus was constructed and tested. It will be used on-line to the SLOW RI radioactive beam facility in RIKEN (Japan) and as in the present experiment for precision absolute frequency measurements of astrophysically important reference lines. In the current work we conducted absolute measurements of spectral lines of Ar ions using parallel and antiparallel geometries. To provide a reference for the laser wavelength iodine saturation spectroscopy was used. The precision of this reference was enhanced by simultaneously observing the beat node between the spectroscopy laser and the corresponding mode of a femtosecond laser frequency comb. When performing collinear and anticollinear measurements simultaneously for the laser induced fluorescence, the exact relativistic formula for the transition frequency v0 = pvcoll � vanticoll can be applied. In this geometry ion source instabilities due to pressure and anode voltage fluctuation are minimized. The procedure of fluorescence lineshapes fitting is discussed and the errors in the measurements are estimated. The result is v0 = 485, 573, 619.7 � 0.3MHz corresponding to (delta v)/v = 6 � 10?10 and is an improvement of two orders of magnitude over the NIST published value.

Thesis (MSc (Physics))--University of Stellenbosch, 2005. / A tunable vacuum ultra-violet (VUV) laser source was recently developed for VUV spectroscopy using state selective excitation and total fluorescence detection. The VUV laser source makes use of a four-wave mixing process to provide tunable VUV radiation for the electronic excitation of the molecules. The theory of four-wave mixing, with the emphasis on parameters that are important for our experimental setup to generate efficient tunable VUV radiation is discussed. The experimental setup, and in particular the metal vapor heat-pipe, which provides Mg vapor as the nonlinear medium, is described. New diagnostic equipment described in this work was added to the experimental setup. This equipment was characterized and utilized together with the existing setup. The additional diagnostic equipment introduced enabled us to measure the tunable VUV output of the source (using a VUV monochromator), making it possible to significantly improve the efficiency of the existing tunable VUV laser source.