This dissertation presents the research on a novel combination of well proven concepts for passive electromagnetic wave-guiding components. The goal of this work is to overcome and minimize losses occurring in frequency-selective structures. The work aims to contribute to an improvement in the application of conventional and Substrate Integrated Waveguide (SIW). It is proposed to mount conventional waveguide structures on the surface of printed circuit boards containing substrate integrated waveguides. The crossover technology is referred to as Surface Mounted Waveguide (SMW). Theoretical investigations are performed, proving the validity and superiority of the proposed structure focusing on the elimination of losses, while maintaining low space consumption and printed circuit board technology compatible manufacturing processes. Additionally, a mode matching technique is developed and successfully applied to prototype such components. The validation of this method reveals superior computational speed when compared to commercial available electromagnetic field solvers. The proposed structures are validated by measurements of several prototypes, including coupled SMW resonator filters, combined SMW and SIW resonator filters, a SMW triple-layer diplexer and single individual SMW resonator filters. The experimental verification shows good agreement between theory and measurements. Moreover, the comparison to other technologies proves the superiority of the proposed structures. / Graduate

Discussion begins with a brief account of atomic level-pumping and reasons why atomic coherence is typically not considered in cw work on optical interactions. This dissertation is divided into four parts: semiclassical treatments of one-photon electric- dipole atom-field single-mode interactions and multimode interactions, and corresponding treatments for the two-photon interaction. We present the effects of injected atomic coherence on the polarization of the medium, the slowly varying envelope wave equation, the single- and multiwave mixing coefficients, and weak field propagation in a homogeneously broadened two-level medium. Spatial and temporal phase matching of the injected coherence to a field mode is crucial throughout, since the field may not be able to remain in phase with the induced and injected polarizations. One-photon injected coherence contributes directly to the polarization at the atomic resonance frequency. The perfectly phase-matched case leads to a linear superposition of an exponentially decaying field (Beer's law) and a constant field driven by the injected coherence. The interaction of an injected coherence with a detuned field produces frequency-symmetric sidebands about the pump field polarization. The sideband spacing equals the atom-field detuning. To probe the injected coherence we inject a weak resonant field. The resulting three-wave mixing leads to multiwave mixing coefficients that are unaffected to first-order in the weak sidemodes, but the injected coherence adds inhomogeneous terms to the coupled-mode equations. For both single- and multimode interactions the injected coherence does not affect the exponential growth/decay of the sidemodes, but it supports a weak field that may propagate if properly phase matched. For two-photon media the injected coherence requires at least one field interaction in order to produce a polarization, which then appears in the single- and multiwave mixing coefficients. The exponential growth/decay rate is modified by the injected coherence. For a centrally-tuned pump the injected coherence contributes the standard multiwave mixing terms as well as additional effects. Four-wave mixing is discussed as a means of relaxing the spatial phase matching constraint on the injected coherence.

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In this thesis, I describe the first calibration of the T2K ND280 electromagnetic calorimeter using cosmic muons. T2K is a long baseline neutrino oscillation experiment whose main aim is to observe for the first time the νμ→νe oscillations. A complete understanding of the νμ disappearance or νμ→νx oscillations, x = μ or τ , and neutrino-nucleon interactions will complete the T2K physics programme. T2K produces an intense muon neutrino beam at the J-PARC facility on Japan's East coast. This neutrino beam is then detected twice: once 280 m from its start by ND280 - whose purpose is to characterise the beam - and then again 295 km away at the far detector SuperKamiokande on the West coast of Japan. One of the components of the ND280 detector is the electromagnetic calorimeter. A thorough understanding of the electromagnetic calorimeter is crucial. In this thesis I first describe the quality assurance of the photosensors used in the calorimeter. Then I describe the cosmic muon flux simulation, that I adapted from CORSIKA for the electromagnetic calorimeter studies, and now adopted by the whole T2K collaboration. This is followed by a description of calibration of the calorimeter using the cosmic muon flux, in particular the light yield attenuation, and finally the comparison of the results obtained with cosmic muons taken at two different locations, CERN and Tokai. Moreover, I describe the ND280 Workbook, an online guide to the ND280 software, including tutorials and information for all the ND280 collaborators, that I developed in its entirety.

It is important that accurate estimates of crew exposure to radiation are obtained for future long - term space missions. To predict the radiation environment, a few space radiation transport codes exist, all of which use basic nuclear cross section information for transport of radiation through materials. Little theoretical and experimental work has been conducted on reactions induced by the electromagnetic (EM) force, especially with regard to di?erential cross sections. Therefore, radiation transport codes have typically neglected to incorporate EM nuclear collision cross sections. EM cross sections for single nucleon removal have been included in some radiation codes, but better values can be obtained by using an energy dependent branching ratio. Most previous theoretical and experimental work has been devoted to total cross sections. Therefore, the energy dependent branching ratios presented can be extensively compared to past theory and experiment. Such comparisons indicate that using energy dependent branching ratios yield better estimates of total cross sections. Differential cross sections for electromagnetic dissociation in nuclear collisions are calculated for the first time. In order to be useful for three - dimensional transport codes, these cross sections have been calculated in both the projectile and lab frames. The formulas for these cross sections are such that they can be immediately used in space radiation transport codes. Only a limited amount of data exists, but the comparison between theory and experiment is good.

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Xu Bai Yu. / "August 22, 2000." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (p. [164]-169). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

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