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- Magnetically Driven Instabilities in Gas Discharges
- In the present experiment a gas discharge plasma generator was designed and constructed and a search was made for evidence of a plasma instability due to the influence of an externally applied magnetic field. The evidence for such an unstable mode of operation is too indirect to make a possible conclusion, but an approach to more certain identification will be indicated.
- The Use of Mossbauer Effect for the Study of Recoilless Rayleigh Scattering of Low-Energy Gamma Rays from Sodium Chloride
- Evidence that recoilless emission and absorption exist may be shown by an experiment in which the source gamma rays are allowed to pass through a suitable absorber to a detector.
- Extinguishment of a Low-pressure Argon Discharge by a Magnetic Field
- The experiment in this study involves the extinguishment of a low-pressure argon discharge by a magnetic field.
- Thermal Properties of a Single Crystal of Bismuth at Liquid-helium Temperatures
- The purpose of this investigation was the determination of the thermal conduction properties of a single crystal of bismuth at liquid-helium temperatures in magnetic fields up to eighteen kilogauss.
- Thermomagnetic Phenomena in Antimony at Liquid Helium Temperatures
- The purpose of this investigation was to study head-transport phenomena in a single crystal of antimony at liquid helium temperatures. In particular, the longitudinal and transverse components of the thermal resistivity tensor were measured as a function of magnetic field up to eighteen kilogauss.
- Electron Transport in Bismuth at Liquid Helium Tempratures
- To obtain information on the band structure of bismuth, galvanomagnetic potentials were measured in a single crystal at liquid-helium and liquid-nitrogen temperatures. These measurements were analyzed for information on the different carriers, particularly for the existence of a high-mobility band of holes.
- Antiferromagnetic Ordering in Picryl-Amino-Carbazyl
- The purpose of the experiment was to investigate other paramagnetic salts to determine whether the W. B. perchlorate type peak was more common than previously suspected. An organic salt, picryl-n-amino-carbazyl, was chosen.
- A Correction Factor for the First Born Approximation
- This thesis looks at a Schroedinger equation and the Born approximation.
- A Computer Analysis of Complex Gamma-Ray Spectra
- The purpose of this investigation was to provide a method for determining the relative intensities of all gamma rays in a particular spectrum, and thereby determine the relative transition probabilities.
- The Diurnal Variation of Cosmic Radiation
- The primary purpose of this investigation was to study the diurnal variation of cosmic-ray intensity.
- Nuclear Magnetic Resonance in a Crystalline Stable Free Radical--Wurster's Blue Perchlorate
- This thesis investigates the nuclear magnetic resonance in a crystalline stable free radical.
- Temperature Dependence of the Magnetic Susceptibility of the Organic Free Radical Galvinoxyl
- This thesis examines temperature dependence of magnetic susceptibility of the organic free radical galvinoxyl.
- Thermomagnetic Effects in Antimony at 4.2 [degrees]K
- The purpose of this investigation was to study the thermoelectric effects in a single crystal of antimony at liquid-helium temperatures.
- A Microwave Spectrometer for Narrow-line Electron Spin Resonance Studies
- This thesis explores the basic theory, design and construction of electron spin resonance spectrometer.
- A Calculation of the Kaon-Neutron Scattering Cross Section
- The purpose of this investigation was to study the scattering processes of K+ mesons with neutrons. In order to do such a study one must first make certain basic assumptions about the type of interaction involved and then proceed to calculate physically meaningful qualities which describe the processes. Thus, the problem is this: assuming the validity of Feynman's rules for these strongly interacting particles, calculate the differential and total scattering cross sections for the interaction of scalar K+ mesons and neutrons.
- Galvanomagnetic Phenomena in Arsenic at Liquid Helium Temperatures
- The purpose of this investigation was to study some of the transport effects in a single crystal of arsenic at liquid helium temperatures in a magnetic field up to twenty-four kilogauss. The experimental coefficients determined were the isothermal magnetoresistivity and the isothermal Hall resistivity.
- Shubnikov-de Haas Effect in Arsenic
- This thesis studies the Shubnikov-de Haas effect in arsenic.
- A Vacuum Tube for an Electrostatic Generator
- The purpose of this study has been to construct two accelerating tubes with small beam apertures for the Van de Graaff, modifying the prototype tube designed and tested by Wiley (20), to design and construct a vacuum system for evacuating the tubes, and to determine the characteristics of the tube under operating conditions while installed in the generator.
- Vertex Functions in K-Meson-Nucleon Scattering
- The purpose of this study was to investigate some theoretical approaches to the scattering of positive k-mesons by nucleons in an attempt to explain the experimental data. In this work the problem has been investigated by the technique of the weak coupling approximation.
- Gamma Rays Resulting from Neutron Scattering in Cesium
- The purpose of this investigation was to attempt to resolve the energy levels of Cs133 that can be excited by inelastic scattering of 14 Mev neutrons.
- Homogeneous Canonical Formalism and Relativistic Wave Equations
- This thesis presents a development of classical canonical formalism and the usual transition schema to quantum dynamics. The question of transition from relativistic mechanics to relativistic quantum dynamics is answered by developing a homogeneous formalism which is relativistically invariant. Using this formalism the Klein-Gordon equation is derived as the relativistic analog of the Schroedinger equation. Using this formalism further, a method of generating other relativistic equations (with spin) is presented.
- A Study and Critique of the Mean Position Concept in Relativistic Wave Mechanics
- The basic concept to be used in studying the question of one-particle interpretations of relativistic wave equations is that of observables and operator representations that are different from the more usual classically motivated observables and representations. In particular, the concept of a mean-position observable will be used to determine to what extent the one-particle "problems" can be resolved.
- Effect of Sample Geometry on Magnetomorphic Oscillations in the Hall Effect in Cadium at Liquid-Helium Temperatures
- This thesis presents observations on size-effect oscillations in the Hall effect in an oriented single crystal of highly pure cadmium at liquid-helium temperatures. All measurements were made in transverse magnetic field.
- The Optimum Design of a Broad-band Helix for Use in Electron Spin Resonance
- This thesis examines optimum designs for broad-band helix to be used in electron spin resonance.
- A Study of the Celestial Gamma-ray Flux
- This thesis is a study of the celestial gamma-ray flux. It reviews several of the proposed mechanisms for producing high energy gamma rays and describes several of the attempts to detect their presence. Also included is a short historical review of the spark chamber, along with a qualitative description of its operation.
- Application of the Wigner Formalism to a Slightly Relativistic Quantum Plasma
- A slightly relativistic fermion gas is described by the dynamical theory obtained from the Wigner distribution function. The problem is approached in a self-consistent manner including the two-body Darwin Hamiltonian. The goal is to find the departures from equilibrium and dispersion relations for wave propagation in the gas.
- Gurevich Magnetomorphic Oscillations in Single Crystals of Aluminum at Helium Temperatures
- The Sondheimer theory was tested by looking for oscillatory phenomena in a group of single crystals representing a range in dimensions from matchbox geometry to thin-film geometry. The single crystals were identical with respect to impurity content, strain, orientation, surface condition, and probe placement.
- Size Effect in the Electrical Conductivity of Bismuth
- If a physical dimension of a metallic specimen is comparable with, or smaller than, the mean free path of the conduction electrons, then the observed electrical conductivity will be less than that of a conventional bulk sample. This phenomenon is called a size effect, and is the result of electron scattering from the specimen surfaces. In the present investigation, measurements were made on electropolished monocrystalline specimens ranging from matchbox geometry to thick-film geometry in order to obtain further information on the size effect in bismuth at liquid helium temperatures.
- Chlorine Nuclear Quadrupole Resonance Absorption of 3, 4, 5, 6 - Tetrachlorophthalimide and 1, 3, 6, 8 - Tetrachloropyrene
- In this study frequency modulation was used with a regenerative spectrometer and a super-regenerative spectrometer to detect the nuclear quadrupole resonance frequencies of chlorine in two commercially available compounds, 1, 3, 6, 8 - tetrachlorophyrene and 3, 4, 5, 6 - tetrachlorophthalimide.
- Galvanomagnetic Determination of Energy Bands in Arsenic
- A study of the transport properties of a substance requires the determination of a set of transport coefficients by experiment. From these coefficients, the elements of the electrical conductivity tensor, thermoelectric tensor, et cetera can be determined. In this experiment, measurements and analyses of galvanomagnetic effects in a single crystal of arsenic were performed. The measurements were made at liquid-helium temperatures in magnetic fields ranging to 25 kilogauss. The gross isothermal, electrical conductivities have been analyzed to determine various parameters characterizing the energy bands in arsenic.
- The Temperature Dependence of Magnetic Susceptibility of Galvinoxyl
- The twofold purpose of this investigation was to design and construct an apparatus for direct magnetic susceptibility measurements as a function of temperature and to provide the complete susceptibility characterization of the free radical galvinoxyl in the room temperature-liquid nitrogen range.
- The Dielectric Constant of Galvinoxyl
- The molecules in many substances are know to undergo at characteristic temperatures a change in their rotational freedom in the solid state, signifying either a change in structure of the material of the onset of limited rotation of the molecule about some symmetry axis. The purpose of this research was to determine from dielectric constant measurements over the 100°K-420°K temperature range whether or not the organic free radical galvinoxyl and its diamagnetic parent molecule, dihydroxydiphenylmethane, undergo any such transitions.
- Boundary Scattering of Electrons in Thin Cadmium Single Crystals
- In the present investigation, zinc was plated onto a cadmium crystal to determine the effect on the scattering parameter.
- Transport Phenomena in Indium Arsenide at Low Temperatures
- This thesis looks at the transport phenomena in indium arsenide at low temperatures.
- Gamma Ray Distribution from Neutron Excitation in Cesium
- The purpose of this investigation was to analyze the gamma rays resulting from excitation of Cs133 by the inelastic scattering of 14 MeV neutrons and to determine the relative intensity of each gamma ray.
- Monte Carlo Calculations of Reflected Intensities for Real Spherical Atmospheres
- To calculate the emergent radiation field, a realistic atmospheric model and algorithm must be developed. The radiation field may be characterized by the emergent intensities of scattered light. This is possible only if the algorithm determines these intensities as dependent upon atmospheric and angular parameters.
- Solutions of the Equations of Radiative Transfer by an Invariant Imbedding Approach
- This thesis is a study of the solutions of the equations of radiative transfer by an invariant imbedding approach.
- Cross-Section at 15.6 and 16.1 MeV
- The intent of this investigation is the determination of the values of the Cs-133 (n,2n)Cs-132 cross-section at neutron energies of 15.6 and 16.1 MeV. Neutrons of this energy are produced with comparative ease by means of the D-T reaction, in which deuterons of energy 500 and 750 keV, respectively, are impingent upon a tritium target.
- Cross Section for the 165/Ho (n, 2n) 164/Ho Reaction at 15.6 MeV
- It was the purpose of this investigation to bring together the ideas and procedures involved in the measurement of (n, 2n) reaction cross sections. Some of the inherent properties of the material under investigation (Holium) are involved in determining these relationships.
- Electron Spin Resonance Absorption in Benzophenone Phenylhydrazone Negative Ion
- This thesis reports an electron spin resonance absorption study of the hyperfine interaction between nuclei and a single "nearly-free" electron in dilute solutions of the benzophenone phenylhydrazone free radical in tetrahydrofuran.
- Magnetomorphic Oscillations in Cadmium Cylinders
- The work presented here is an experimental investigation of the effect of cylindrical geometry on electrical conductivity, in which single-crystal samples of cadmium at the temperature of liquid helium are used, with the diameter on the order of the electron mean free path.
- Microwave Cavity Method for Measuring Plasma Properties
- This discussion is concerned primarily with communications blackout during spacecraft entry into a planetary atmosphere. The gas in the shock layer, between shock wave and vehicle surface, ionizes from the intense heating which takes place in the bow shock wave and a viscous region of high gas enthalpy. This ionization may persist throughout the subsequent flow over the vehicle and into the wake, thus completely engulfing the vehicle and its communications elements. The problem will be to simulate a plasma model that will be of interest for hypervelocity reentry vehicles and to provide meaningful expressions for the various plasma parameters of interest (electron density, electron temperature, collision frequency, etc.) in terms of the microwave measurables (amplitude, phase shifts, frequency shifts, polarization, etc.)
- Recombination Rate Coefficient Measurements in the Helium Afterglow
- This thesis describes a method of determining the recombination rate coefficient experimentally, which does not depend on a specific model of the recombination process. With this method established, results are presented for the recombination rate coefficient measurements at 44.6 Torr.
- Size Dependence in the Electrical Conductivity of Bismuth
- In the present investigation, measurements were made at liquid-helium temperatures on single-crystal bismuth samples which had a stair-step geometry in order to study several thicknesses during one helium run. These samples were also thinned to extend the thickness range of the steps to a thinner region. In addition J.E. Parrott's theory is extended to include a diagonal anisotropic relaxation-time tensor and the effect of holes on the size effect. A discussion of the theory of Parrott, and the extension of Parrott's theory in connection with the experimental results is presented.
- Temperature Dependence of Line Widths of the Inversion Spectra of Ammonia
- One of the purposes of this work is to investigate modifications that have to be made to a standard source-modulation microwave spectrograph so that it can be used to study gases at various temperatures. Another objective in this work is to determine experimentally the function of temperature that describes how the line widths of microwave spectral lines vary with changing temperature. The most important segment of the study is the temperature dependence of the line width since from an accurate knowledge of this temperature dependence one is able to determine what molecular force fields are present and the relative importance of parts of the molecular force field.
- Measurement of the Atomic-oxygen Concentration under Simulated Upper Atmosphere Conditions
- This thesis describes an experimental technique for measuring the atomic-oxygen concentration under simulated upper atmosphere conditions.
- A Precision Angular Correlation Table and Calculation of Geometrical Correction Factors
- In recent years y-y angular correlations have been very useful in confirming the spins of excited nuclear states. Angular correlation techniques have also been employed to study the electric and magnetic character of excited nuclear states. With these things in mind, it was decided to design, construct, and test a precision angular correlation table.
- The Effects of Lead Placement and Sample Shape in the Measurement of Electrical Resistivity
- This thesis is a study of the effects of lead placement and sample shape in the measurement of electrical resistivity.
- Magnetomorphic Oscillations in Zinc
- In making this study it is important to search for ways to enhance and, if possible, make detection of MMO signals simpler in order that this technique for obtaining FS measurements may be extended to other materials. This attempt to improve measurement techniques has resulted in a significant discovery: the eddy-current techniques described in detail in a later section which should allow MMO to be observed and sensitively measured in many additional solids. The second major thrust of the study has been to use the newly discovered eddy-current technique in obtaining the first indisputable observation of MMO in zinc.
- Carbon Contamination Measurements in Single Silicon Crystals
- The intent of this investigation was to directly measure the amount of carbon contamination in a single silicon crystal and, in so doing, develop a mathematical procedure that would be applicable to other contaminants in other substances.