Physics Commons^™

Electron Transitions In Multiply-Charged Ion-Helium Collisions, M. Lou Mckenzie

Masters Theses

"A classical model for He using the Classical Trajectory Monte Carlo method is developed to study multiply charged ions colliding with He at intermediate energies. Reactions studied are single and double electron capture and ionization and electron capture-ionization for projectile charge states q = +1 to +50. The dominant collision process is single ionization. Charge exchange is found to be a two-electron process, where one electron is ionized and one is captured by the projectile. We find our calculations to be in good agreement with available experimental data, supporting our interpretations of the collision mechanisms"-- Abstract, p. iii

Conductivity And Photoconductivity Mechanisms Of Iron And Magnesium Doped Lithium Niobate, Joseph Francis Kirchhoff

Masters Theses

Various compositions of lithium niobate crystals were observed to have an electrical conductivity given by 2.3 x 10³ exp(-1.21/kT) Ω^-1 m^-1 between 200 and 3 15°C. This implies that in this temperature range, all such crystals exhibit comparable carrier concentration and mobility. A model based on intrinsic conductivity is presented which adequately agrees with experiment. In addition, a model is presented by which electronic photoconductivity can be predicted by evaluating the trapping cross-section associated with Fe³⁺ ions dependent upon their lattice sites"-- Abstract, p. ii

The Homodyne Interferometer And Its Use In Finding The Optical Properties Of Graphite, Steven Randle Frey

Masters Theses

"An interferometer based on the principle of homodyning can be used to measure the reflectance of solid samples at microwave frequencies. These measurements provide the low frequency values needed for a Kramers-Kronig analysis. This analysis yields the complex dielectric function, e₁⁺ ie₂, and complex index of refraction, n + ik, of the solid. 2 This interferometer was tested on a pressed pellet sample of powdered Dixon 200-10 graphite and yielded satisfactory results. Also investigated were two different methods of signal modulation: mechanical chopping and a rotating wire grid polarizer" Abstract, p. ii

Direct Memory Acquisition Of Fast Analog Signals, Syed Javaid Iqbal

Masters Theses

A fast data transfer computer circuit is developed using the direct memory acquisition (DMAC) technique. For this purpose Z-80 microcomputer ·chips, manufactured by Ziolog, were used. The direct memory acquisition circuitry was developed in several stages and required both hardware and software development. An erasable programmable read only memory (EPROM) programmer was built for reading and loading the system program. The design, construction, and testing of the DMAC system are discussed in detail and an example of the use of this system for collecting data is given.

The Design And Construction Of Microprocessor-Computer Controlled Rapid Scanning Fiberoptic Spectrophotometer, Kathleen Marie Tobin

Masters Theses

Conventional spectrophometers require the transfer of a sample to a cuvette for obtaining spectra. The measurement of absorbance in situ can be accomplished using a fiber optic probe which can be placed directly in the sample. The fiber optic probe also minimizes environmental factors such as thermal or vibrational which may affect the absorbing species. A rapid scanning speed allows for essentially simultaneous wavelength monitoring.

The effect of coupling a rapid scanning spectrophotometer with a fiber optic probe provides for an extremely versatile system. When used in comjunction with a microprocessor or computer, this approach offers advantages such as data …

A Study Of Integral Equations For Computing Radial Distribution Functions, Zainuriah Hassan

Masters Theses

Integral equation T (a two parameter equation of the Ornstein-Zernike form) is studied for computing the radial distribution functions of simple classical fluids interacting pairwise according to the Lennard-Jones 6-12 potential function. Numerical calculations are done on a computer for the system in the gas and liquid phases. At a high temperature, equation T results are found to agree very well with equation C when the parameters are chosen in a similar way. At a temperature slightly above the critical temperature, results from other sources over a wide density range. In equation T, by varying two of the parameters, the …

The Pauli Operator Correction In The Effective Λn Interaction, Jaleh Owliaei

Masters Theses

Hypernuclear structure calculations performed for ⁶_ΛLi, ⁷_ΛLi, and ¹⁶_Λ0 have reproduced the 1_Λ=1 levels inferred from the recent (k, Π) reactions. However the 1_Λ=0, groundstate of ¹⁶_Λ0 is overbound by 6 MeV in these calculations, indicating a density dependence in the effective ΛN interaction in the interior of the heavier system. In this work corrections to the ¹⁶_Λ0 effective interaction are introduced in terms of a Brueckner-Goldstone G-matrix with a modified Pauli operator. The G-matrix of ¹⁶_Λ0 derived from that of ⁶_ΛLi …

The Impeachment And Trial Of Secretary Of War William Worth Belknap, Duane Edward Holthof

Masters Theses

The purpose of this thesis is to give an account of the events which lead to the resignation of Secretary of War William Worth Belknap in 1876, to examine the circumstances surrounding his impeachment, and to study the testimony in his Senate trial.

Although Belknap was not convicted on charges of accepting bribes, most of those senators who voted to acquit him did so on the technical ground that the Senate lacked the jurisdiction to try a private citizen. The evidence in the case clearly indicated Belknap's involvement, and there seems little doubt that if Belknap did not know what …

Construction And Testing Of A New Atomic Physics Beam Line At The Western Michigan University Accelerator Laboratory, William Andrew Hollerman

Masters Theses

A new beam line containing a differentially-pumped gas cell and charge state analyzing magnet was constructed for the purpose of measuring a wide variety of atomic inner-shell processes, such as excitation, ionization, and charge transfer. The completed system will be able to measure these individual atomic processes using coincidence techniques. Initial testing of the beam line was performed using 40MeV S⁺⁷+Ar collisions to determine the effect of the collimating slit size on the measured x-ray cross sections. These measurements showed that the slip size on the measured x-ray cross sections. These measurements showed that the slit size affects …

Resonant Electron Transfer And K-Shell Excitation Of Lithiumlike Projectiles In Collisions With Neutral Gas Targets, Carollyn Sloan Oglesby

Masters Theses

No abstract provided.

A Study Of Integral Equations For Computing Radial Distribution Functions, Robert C. Scherzer

Masters Theses

The use of integral equations to find radial distribution functions for computing thermodynamic properties is examined. The system considered is a simple classical fluid with interactions according to the Lennard-Jones (6-12) pair potential function. Two parametric integral equations (C and T) are studied in detail. Derivation of equation T and a power series solution are given. Computer solutions at several different temperatures, densities, and parameter values are obtained. Comparisons are made betv/een these results and results from integral equation N, PY, and HNC, and results from Monte Carlo, molecular dynamics, and power series methods. Equations C and N are found …

A Quantitative Study Of The Copper Content In Granite Rocks, Samir F. Al-Mandwee

Masters Theses

A spectrographic analysis was conducted on ten granite samples of different geological origin from the Pioneer Mountains in Central Idaho. A qualitative analysis was performed first and then a quantitative analysis to determine the presence and relative amounts of copper in the various samples. This spectrographic analysis employed a direct current arc source of 340 volts and 4 amperes to excite the samples which were dissolved in acid and dried on the ends of high purity carbon electrodes. The emitted light passed through a step sector and a medium quartz spectrograph to a photographic plate. The optical density of the …

The Special Theory Of Relativity In A Gravitational Field, Masayuki Note

Masters Theses

"A theory is presented which generalizes the special theory of relativity to an acceleration field. The theory is based on the re-interpretation of linear motion as an acceleration field and is applied to a gravitational field. It is shown that the theory explains the precession of Mercury's perihelion and the deflection of light near the sun"-- Abstract, p. iv

Non-Equilibrium L-Shell Effects On K-Shell X Rays For 20-54 Mev S+C Collisions, Donald Solon Shippy

Masters Theses

Projectile K x-ray yields have been measured as a function of target thickness (2.0-150 μg/ cm²⁾ for 20-54 MeV S^q+ ions incident on this carbon foils using the WMU EN tandem Van de Graaff accelerator. The measured K x-ray yields were fond to increase for thicknesses < 15 μg/cm² and decease for thicknesses > 15 μg/cm² . The increasing yield is attributed to L-Shell non-equilibrium as the ion traverses the foil, while the decreasing yield is attributed to K-shell non-equilibrium. Analysis of the data was performed by modifying the "two-component" model of Betz et al. to include the effect of …

Application Of The Impact Approximation To Collisional Line Shifts In Na-Rare Gas Systems, Mahdi Azougui

Masters Theses

"This dissertation deals, mainly, with the line shifts of the excited atoms of sodium induced by collisions with argon atoms. The general work is based on the study of both, broadenings of the lines and line shifts with a particular emphasis on the latter. A review is given for the case of very large principal quantum numbers N; then the binary collision method is detailed for low transitions (N ≤ 6) where the computed values are in very good agreement with the experimental results obtained by Krebs and Schearer.¹ This method breaks down at larger N. Next, a modification …

A Laser Interferometric Study Of Electric Field Effects On Methane-Oxygen Flame Plasmas, Mark D. Prairie

Masters Theses

A laser interferometer is developed to study the refractive index field, aerodynamic structure, and three dimensional temperature profile of a methane-oxygen flame system under the influence of D.C. electric fields. A combined graphical-numerical method is used to transform the observed interference patterns into radial temperature distributions. The results indicate that the electric field exerts a marked influence on the flame stability, geometry, and charged particle flow. Experimental evidence shows that these effects are most apparent under fuel rich conditions. It is suggested an electric field may change the concentration gradients of reacting species, leading to an altered course of fuel …

Detector Geometry For Cascade Photon Experiments, Roger Minoru Munechika

Masters Theses

An observation of cascading optical photons can be used to determine an absolute excitation cross section for the intermediate state without the need of standard lamp calibration. In order to reduce the data an angular correlation function and an angular distribution function must be known. These functions depend on the alignment of the upper excited state and the polarization of the light emitted in the lower part of the cascade. However, at certain angles of observation the values of the required functions are known regardless of the alignment or polarization. A computer search is done to find these angles for …

A Study Of The Films Produced By The Aluminum/Water Reaction Using Rutherford Backscattering Spectroscopy, Reed L. Shilts

Masters Theses

This work compares the action of pure water to various aqueous electrolytes on aluminum surface film formation at about 100°C. The electrolytes were pure water with various inhibitor ions added. The ions were nitrate, tungstate, borate, molybdate, silicate, phosphate, a mixture of nitrate and molybdate, and a mixture of silicate and molybdate. The investigative technique was Rutherford backscattering spectroscopy (RBS) using 2 MeV alpha particles with an annular detector set at 180 degrees for maximum elemental resolution. RBS was chosen for this investigation because it offers in an easily interpretable manner a relatively fast and semi-quantitative method of analysis of …

The Creation Of Holograms Utilizing Fiber Optics, Abdul Rahim Omar

Masters Theses

Holography involves the interference of two light beams, namely a reference beam and an object beam. Instead of the conventional method using beam splitters and mirrors to direct the light path, fiber optic bundles are used and high quality holograms have been produced. When fiber optic bundles are used, a spatial filter is not needed to produce a "clean" beam of light for the reference beam. Fiber optic bundles also provide greater flexibility of illumination for the object beam and/or fir the reference beam. Also, it is easier to illuminate the object from many directions. Finally, the distance from the …

A Study Of The Target Thickness Effect For Chlorine On Germanium From 25 To 49.5 Mev, James Robert Slusser

Masters Theses

No abstract provided.

Development Of A System For Water Quality Analysis Using Particle Induced X-Ray Emission, James Albert Andrus

Masters Theses

Particle induced x-ray emission (PIXE) has been in use for several years at Western's accelerator laboratory. Its primary purpose has been to provide trace element analysis of various types of solid samples. The analysis of water samples has not been done because of problems involving target preparation for the accelerator. A process called vapor filtration, developed at Purdue University, allows adequate sample preparation for the accelerator. This process is being adapted for use here at WMU. When completely operational, this system will give the WMU accelerator program the additional capability of performing water quality analyses to concentrations of parts per …

The Neutron Total Cross Section Of 208Pb, Lawrence J. Satkowiak

Masters Theses

No abstract provided.

Photoconductivity And Photovoltaic Studies On Some Ii-Vi Compounds, Challa Nagesh

Masters Theses

The photoconductivity spectra of ultra-pure single crystals of CdS in the range 500-575 nm, CdSe in the range 700-900 nm, ZnSe in the range 420-570 nm and ZnS in the range 300-450 nm have been studied using an improved A.C. method of detection. The sensitivity of the apparatus is high enough to study weak photoconductors like ZnS. The photoconductivity spectrum of each substance showed a peak at the wavelength corresponding to the energy band gap of the substance. The energy band gaps obtained from the spectra are 2.35 eV for CdS, 1.6 eV for CdSe, 2.7 eVfor ZnSe and 3.6 …

Nmr Instrumentation With Solid State Devices, Syed M. Ahmed

Masters Theses

No abstract provided.

A Feasibility Study Concerning The Use Of Alternate Energy Sources In Taiwan, Li-Juan Lee

Masters Theses

No abstract provided.

Theoretical Thermodynamic Functions For Krypton Gas, A-Hamid Aidinejad

Masters Theses

No abstract provided.

Generalization Of The Form Of The T Matrix Operator Of Non-Relativistic Scattering Theory, Francis Leone

Masters Theses

No abstract provided.

Analysis Of Chert By Particle Induced X-Ray Emission, Jeanette E. Gibeson

Masters Theses

No abstract provided.

Method Of Variational Secular Equation For The Ground State Of Helium Atom, Mih-Seh Kong

Masters Theses

No abstract provided.

Spin-Flip Inelastic Scattering In 12C(P,P1)12C Near The 9.14 Mev Doublet, Hsing-Tsuen Chen

Masters Theses

No abstract provided.