The entire sixteen element scattering matrix for two parallel dielectric fibers over an angular range of θ = 5°-170° as measured from the forward θ = 0 direction has been experimentally measured using the polarization modulation technique. Experimental results were in good agreement with theory for light scattering from two parallel fibers. Measurements were made for both endside and broadside illuminations at normal incidence for fibers at various separations from 2 μm to 70 μm. Laser wavelengths used were 632.8 nm and 441.2 nm, and fiber radii were 0.400±0.002 μm, 0.370±0.002 μm, 0.428±0.002 μm, and 0.406±0.002 μm. Special care was taken to measure the fiber radii, fiber separation, and to establish the parallelism between the two fibers. Electrostatic attraction between the fibers prevented the investigation for separation below 2 μm. A vibration detection device based on two-fiber light scattering has also been suggested.

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"A novel approach to a light scattering experiment that employs a lounge image capture assay has been developed for both static and dynamic measurement on a wide variety of samples. In this work, the 'Development and Application of an Area Recorded Generalized Optical Scattering Technique', abbreviate as ARGOS, an approach is based on the placement of a translucent screen where the scattered light, now converted to a diffuse light, is imaged as a function of time. The placement and size of the screen determines the range of scattering wave-vectors, while the time between images determines the fastest dynamic resolvable . The overall experimental stability determines the slowest dynamic resolvable and so can be made arbitrarily long. The scattering intensity is measured by a camera whose dynamic range (number of bits per pixel), resolution, and speed determines the sensitivity and accuracy of intensity of the scattered light. The system allows for an extremely well-defined scattering experiment geometry, where images may be manipulated to extract structure (i.e. average I(q)over t) and dynamics (average I(q,t) over q) for a wide range of samples(liquids and solids). A number of innovation were developed. Instead of a beam stop to block the high intensity thru-beam, a thru-beam attenuator was developed such that the exact center of the scattering geometry is determined for each image acquired. A variety of image processing algorithms were also developed to correct for dead pixels, camera response, and intensity normalization. Of particular use was the development of the root-mean-square difference(RSD) image to probe dynamic. Here, the first image is taken as the time-zero reference image and subtracted from all succeeding images where averaged over a speci ed q and plotted as a function of time revealing the build up image changes due to dynamics. The technique was validated for both static and dynamic measurements with a set ofdilute suspended latex spheres in water (sizes ranging from 0.01 to 2micro m). The static light scattering result in terms of particle radius and dimension closely matched the expected values. The dynamic light scattering results could only several the end of the dynamics of these suspended latex spheres due to Brownian motion because of the speed limitation of the camera. However, sedimentation dynamics that are much slower, were early observed. The ARGOS technique was then applied to two biological systems, the evolution of a dilute suspension of E. Coli bacteria through the life-cycle and the evolution of the same suspended bacteria but infected with the MS2 bacteria-phage virus. High temporal resolution data were obtained of the bacteria life-cycle which werecorrelated with size, structure, and dynamics that revealed potentially new insights on behavior not well understood in the literature . The MS2 infected bacteria revealed the effect of the bacteria-phage on every character of the E. Coli life-cycle. The successful development and implementation of ARGOS here has also revealed avenues to greatly improve the performance."

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Ng, Kin Sang = 球狀液滴的彈性光散射,包括高階彩虹、炫光點及形態相關共振的數值計算與實驗研究 / 吳健生. / Thesis submitted in: October 2007. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 101-104). / Text in English; abstracts in English and Chinese. / Ng, Kin Sang = Qiu zhuang ye di de tan xing guang san she, bao kuo gao jie cai hong, xuan guang dian ji xing tai xiang guan gong zhen de shu zhi ji suan yu shi yan yan jiu / Wu Jiansheng. / Acknowledgements --- p.i / Abstract --- p.ii / Table of Contents --- p.iv / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Brief history --- p.1 / Chapter 1.2 --- The theory of rainbow --- p.4 / Chapter 1.2.1 --- Rainbow position --- p.4 / Chapter 1.2.2 --- Airy theory --- p.6 / Chapter 1.3 --- Glare points --- p.9 / Chapter 1.4 --- Mie scattering theory and Debye series --- p.11 / Chapter Chapter 2 --- Interference of the nth- and higher-order rainbows --- p.16 / Chapter 2.1 --- Introduction --- p.16 / Chapter 2.2 --- Interference of overlapping rainbows --- p.18 / Chapter 2.3 --- Results and discussion --- p.20 / Chapter 2.3.1 --- Glare point intensity of group G(ll) --- p.20 / Chapter 2.3.2 --- "Glare point intensities of groups G(8), G(9), and G(10)" --- p.24 / Chapter 2.3.3 --- Effects of varying acceptance angle --- p.27 / Chapter 2.3.4 --- Comparison with results of Lock and Woodruff --- p.29 / Chapter Chapter 3 --- Glare points of high-order rainbows --- p.30 / Chapter 3.1 --- Introduction --- p.30 / Chapter 3.2 --- Results and discussion --- p.32 / Chapter 3.2.1 --- Glare points formed by rainbows of a particular order --- p.32 / Chapter 3.2.2 --- Glare points obtained by plane wave calculation --- p.42 / Chapter Chapter 4 --- Elastic light scattering from droplets embedded in gelatin --- p.45 / Chapter 4.1 --- Introduction --- p.45 / Chapter 4.2 --- Motivation --- p.48 / Chapter 4.3 --- Experimental Preparations --- p.51 / Chapter 4.3.1 --- Sample preparation --- p.51 / Chapter 4.3.2 --- Measurement of refractive index of gelatin --- p.53 / Chapter 4.4 --- Observation of morphology-dependent resonances by varying wavelength of incident laser light --- p.56 / Chapter 4.4.1 --- Experimental setup --- p.56 / Chapter 4.4.2 --- Results and discussion --- p.58 / Chapter 4.5 --- Observation of morphology-dependent resonances by varying temperature of droplet --- p.70 / Chapter 4.5.1 --- Experiment --- p.70 / Chapter 4.5.2 --- Results and discussion --- p.73 / Chapter 4.6 --- Scattered light intensity as a function of scattering angle --- p.77 / Chapter 4.6.1 --- Experiment --- p.77 / Chapter 4.6.2 --- Results and discussion --- p.79 / Chapter Chapter 5 --- Conclusion and future outlook --- p.89 / Appendix Program dave.for Listing --- p.92 / References --- p.101

Theoretical investigations of electron-inert gas scattering are challenging because of the complex target structure. The electron-Helium system has been the most studied both at low and intermediate energies by sophisticated R-matrix and coupled channels methods. For the other inert gases, few calculations have been attempted at the same level sophistication. One problem is that general target-structure codes provide different forms of wave functions that must be interfaced with the scattering equations. The theoretical work presented in this thesis is based on the momentum-space coupled channels equations. For this formalism only one and two-electron atoms have been studied and purpose-built routines, specific to these atoms, have been developed. For the inert gases however such a task is much more formidable and a more practical approach is to use existing structure codes that have taken several man-years to develop. The framework of this thesis comprises of two parts. In the first part we discuss the need for, and the way to, modify the existing close-coupling code developed by Berge & Stelbovics in order to interface with other atomic structure packages in the literature. Two mainstream packages, an atomic structure package of Charlotte Froese Fischer and an atomic structure of Alan Hibbert are discussed. Methods to extract the wave functions for Helium and Neon targets using Hibbert's package are given. In the second part, various options and strategies for the calculation of the target structure, including frozen-core and configuration-interaction wave functions, using analytic Slater, Laguerre or numerical orbitals are considered for the Helium target. Hibbert's structure code wave functions are shown to be correctly interfaced into our momentum-space coupled channels code. The pros and cons of the various target structure descriptions are given and applied for lowenergy elastic and inelastic scattering of electron from Helium.

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