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The Elastic Scattering Of 1.33 Mev Gamma Rays From Tin, J. Edward Terdal

Masters Theses

No abstract provided.

The Mossbauer Effect In Ferric Stearate And Ferric Oleate, Ronald L. Wilson

Masters Theses

No abstract provided.

Angular Correlation Of Positron Annihilation Radiation In Damaged Nickel And Iron, Hsien Chen Huang

Masters Theses

No abstract provided.

Inelastic Deuteron Scattering From 151Eu, Gerald Ralph Boss

Masters Theses

No abstract provided.

Fission Barriers And Transition-State Spectra For 232th, 234th, 238u, 240u, 242pu, And 244pu From 9t, Pf0 Reactions., James D. Cramer

Physics & Astronomy ETDs

Joliot and Curie’s discovery of artificially induced radio-activity in several nuclei by a-particle bombardment encouraged Fermi and his collaborators in 1934 to attempt similar experiments using neutron bombardment of various target elements/ Using natural uranium as a target material they discovered at least four radioactive products, assumed to be elements in the transuranium region. These experiments were repeated in 1937 by Meitner, Hahn and Strassman in Germany where they found that some of these radioactive elements produced by neutron bombardment of uranium had barium-like chemistry, and were assumed to be isotopes of radium. Further investigation proved that these products could …

Standing Waves On The Moon, Lewis T. Chadderton, Frans G. Krajenbrink, Robert Katz, Arcadio Poveda

Robert Katz Publications

The existence of local annular and radial structures in the environment of lunar craters, and of a global selenographic tectonic pattern, is ascribed in part to standing “moonquakes” established after impact or eruption.

A Calculation Of Photodetachment From Molecular Oxygen, Raymond Pollock Jr.

Physics & Astronomy ETDs

The problem of photodetachment from homonuclear diatomic mole­cules is treated theoretically, with the aim of providing a calcula­tion of photodetacbment from the molecular oxygen ion. Using a two­-center (spheroidal) coordinate system a one-electron model including direct coulomb, polarization, and approximate exchange interactions is developed, and formulas for scattering and photodetachment cross section are derived. Wave functions representing both bound and free electrons in the field of the neutral molecule are calculated numerically, using adjustable parameters in the exchange and polarization potentials to attain the proper binding energy. The photodetachment cross section is then computed from these wave functions, along with …

An Attempt To Measure The Diffusion Of Aluminum Into Natural Aluminum Oxide, Charles Edward Galaspie

Master's Theses

The goal of this research was to investigate the diffusion of aluminum ions in natural aluminum oxide grown under atmospheric conditions. The basis for the approach employed here had been developed earlier by J. H. Christian and H. L.Taylor. However, these authors studied the diffusion of aluminum ions in an oxide grown in a pure oxy­gen atmosphere. They utilized a glass slide upon which aluminum metal was deposited in vacuo (10^-11 Torr). Oxide was then allowed to grow on this metal by back-filling the vacuum with pure oxygen to a pressure of 40 to 50 m Torr while infrared …

Decay Of The (2S22P)2P Compound State In Helium By Two-Electron Emission, Paul Burrow, G.J. Schulz

Paul Burrow Publications

Compound states of atoms are known to decay by the emission of a single electron into many states lying at lower energies. Compound states associated with doubly excited states lie at energies above the ionization potential, and therefore the decay into an ion by the emission of two electrons is energetically possible. This paper presents evidence for such a two-electron decay in the case of the (2s²2p)^2p compound state of helium which derives from the (2s²)¹S atomic state.

Spectrophotometric System For Transient Observation Of Solids Under Pulsed Electron Irradiation, R.T. Williams, Robert Fuller, M.N. Kabler, V.H. Ritz

Robert G. Fuller Publications

THE purpose of this note is to describe a relatively simple apparatus for measuring the properties of transient optical absorption and emission bands in solids under pulsed irradiation. The equipment is presently being for the electron beam. The electron beam traverses a 28 cm air path between the exit window of the electron accelerator and the titanium Dewar window. The sample is mounted in vacuum on the Dewar cold finger approximately 3 cm behind the Dewar window. Under these conditions a single electron pulse will deposit 10¹⁷ eV/cm² in the sample. This generates an easily detected transient absorption …

A Nonsecond Time-Of-Flight Spectometer, David Moorman

Masters Theses & Specialist Projects

The purpose of this thesis was to construct a time-of-flight spectrometer using plastic scintillators coupled to photomultiplier tubes as the primary detectors. A time-of-flight spectrometer with at least 2.0 nanoseconds of time resolution was desired.

Electrical Conductivity & Seebeck Effect In Activated Molybdenum Oxide Hydrogen Detectors, John Hooker

Masters Theses & Specialist Projects

This thesis describes the results and analysis of Seebeck coefficient and electrical conductivity measurements on "activated", molybdenum-oxide, thin film hydrogensensing elements. The work was undertaken in an effort to produce data that would be useful in obtaining an understanding of the electronic processes which cause large electrical conductivity changes in molybdenum-oxide upon exposure to small concentrations of hydrogen in air. The results are analyzed using a simple band model of a semiconductor. This model is shown to give reasonable results at high temperatures; however, a departure from the usual .! model is required in order to explain the results at …

High-Field Galvanomagnetic Properties Of Aual2, Auga2, And Auin2, J.T. Longo, P.A. Schroeder, David J. Sellmyer

David Sellmyer Publications

Measurements of the magnetoresistance and Hall voltage have been made in the high-field region on the metallic fluorite compounds AuAl₂, AuGa₂, and AuIn₂. The results have been compared with those expected from the nearly-free-electron (NFE) model. These compounds are uncompensated. The magnetoresistance measurements in principal planes and directions, with one exception, support the NFE model, but the dimensions of the two-dimensional areas of aperiodic open orbits show pronounced deviations. Hall-effect measurements for B in the 〈100〉 and 〈111〉 directions indicate significant departures of the real Fermi surface from the NFE model. A proposed empirical …

L And M Auger Spectra For Silver, Samaa Naga El Ibyari

Archived Theses and Dissertations

No abstract provided.

Directional Correlation Of The 346-136 Kev Gamma-Gamma Cascade In Ta¹⁸¹, Robert Allan Wilson

Dissertations and Theses

The directional correlation of the 346-136 Kev gamma-gamma cascade in Ta¹⁸¹ was measured using the delayed coincidence method with a source of Hf¹⁸¹ in 27 N HF. The contributions to the composite delayed coincidence spectrum of the interfering 133-482 Kev and 133-346 Kev cascades were removed by the subtraction from this spectrum of appropriate 133-482 Kev pure delayed coincidence data. The extracted 346-136 Kev coincidence data then yielded the correlation coefficients A₂₂ = 0.190±0.011 and A₄₄. = -0.025±0.024 that are consistent with the established spin sequence 5/2(E2)9/2(M1 + E2)7/2 and with an admixture of 16.2%±1. 2% E2 radiation in the …

The Monte Carlo Method Applied To An Estimation Of Delayed Neutron Response, Garland David Turner

Physics & Astronomy ETDs

An experimental program has been undertaken at Los Alamos Scientific Laboratory to study delayed neutron effects. As a part of this program, experiments were conducted with thin disks of various fissionable materials to measure the delayed neutron response to a pulse of high-energy neutrons. In support of the experiments, calculations were made with a computer program which solves the Boltzmann transport equation by finite difference methods. Difficulties with the calculations led to an analysis showing that correct treatment of neutrons moving parallel to the faces of the disk was vital to the success of the calculation. As an extension of …

Cosmic Ray Anisotropy In Interplanetary Space, Jacqueline Hope Ericksen

Physics & Astronomy ETDs

The solar diurnal variation of cosmic ray intensity results from an interaction of cosmic rays with the co-rotating spiral interplanetary magnetic field. Changing interplanetary conditions might therefore be reflected in the diurnal variation. In this dissertation, the dependences of the quiet-day solar diurnal variation on the general level of solar activity and on the interplanetary sector structure are investigated. It is found that the amplitude of the solar diurnal variation as recorded by the Embudo and Bolivia multidirectional underground muon telescopes is significantly smaller near solar minimum (1965) as compared to solar maximum (1968). This amplitude dependence is associated with …

Theoretical Determination Of The Spectroscopic Constants Of The H₂ Ground State, Fun-Min Wu

Physics & Astronomy ETDs

Recently the h2 ground state potential E was calculated in double precision by Kolos and Wolniewicz using a 1oo-term wave function. For this kw potential the coefficients in a power series expansion about the potential minimum re are here determined by using the pure electronic potential and central differences. Resulting Dunham potential coefficients Ao, A1, A2, A3, A4, A5, and A6 are 79703 cm-1, -1.6031, 1.865, -1.999, 2.048, -2.02 and 2.0, respectively. From these coefficients the spectroscopic constants are found to be yoo = 8.36, y10 = 4406.6, y20 = -122.6, y3o = 1.2, y40 = -0.04, yo1, = 60.838, …

Lattice Dynamics Of Naf, Arnold Karo, John R. Hardy

John R. Hardy Papers

The results of an extended calculation of the normal modes of the NaF lattice are presented. Three models have been considered : a "rigid-ion" (RI) model, a "deformation-dipole" model with central F^--F^- short- range interactions (DDNNN), and a “deformation-dipole" model including both central F^--F^- interactions and a noncentral component in the first-neighbor, short-range interactions [DDNNN(NC)]. For each of these models we have derived frequency spectra for both 300 and 0°K input parameters, the associated dispersion curves for symmetry directions, Debye characteristic temperatures Θ_D, moment functions ω_D(n), and the …

High-Field Studies Of Band Ferromagnetism In Fe And Ni By Mössbauer And Magnetic Moment Measurements, S. Foner, A. J. Freeman, N. A. Blum, Richard B. Frankel, E. J. Mcniff, Jr., H. C. Praddaude

Physics

High-field susceptibility χ_HF in Fe and Ni (at 4.2, 77, and 300°K) and high-field Mössbauer studies in Fe at 4.2°K are reported and related to the band structure of Fe and Ni and to band models of ferromagnetism. The Mössbauer effect was employed to measure the change in the hyperfine field H_n at the ⁵⁷Fe nucleus with application of an external field. Assuming H_n to be proportional to the bulk magnetization, a microscopic equivalent to χ_HF is obtained. We also show how the high-field data may be used alternatively to determine the nuclear g factor. …

Theoretical Investigations Of The Vibrational Spectra Of Boron Oxide Glass, Zaven K. Altounian

Archived Theses and Dissertations

No abstract provided.

Analysis Of The Vibrational Modes Of The Triborate Anion, Panayiotis Th. D. Sphicas

Archived Theses and Dissertations

No abstract provided.

A Study Of The Sidereal Diurnal Variations Of Cosmic Rays Underground., Albert Brunsting

Physics & Astronomy ETDs

The sidereal diurnal variation of cosmic rays has been measured using underground (40 m.w.e.) meson telescopes located near Albuquerque, New Mexico (35.20°N, 106.41°w) and at Chacaltaya, Bolivia (16.31°s, 68.15°w). Each ofthe two locations has telescopes which scan the vertical and four inclined directions.

Two and three complete years were used for the tele­scopes at the Bolivia and New Mexico locations respectively. The average solar diurnal variations were calculated for each telescope for each month. Based on these monthly averages, the sidereal diurnal variations were computed. A correction was made in the analysis for any yearly modulation of the solar diunal …

Steady-State And Transient Currents In Organic Liquids By Injection From A Tunnel Cathode, Pavel Smejtek, David G. Onn, M. Silver

Physics Faculty Publications and Presentations

Experimental data are presented on the currents induced in organic liquids by injection from a tunnel cathode. The injection level was varied over a wide range resulting in almost no space‐charge limitation to almost complete space‐charge limitation. Results were different from that usually observed in solids, in that at low fields, the steady‐state current was proportional to V², while at high fields the current was proportional to V. By proper choice of electrode spacing and applied voltage, space‐charge‐limited current transients as low as 10⁻¹¹ A∕cm² and 5 sec transit times were observed. A smooth transition between the electrode‐limited and the …

Fabrication Of Lithium Drifted Germanium Detectors Of Planar Structures, Khin M. Yin

Masters Theses

No abstract provided.

Elastic Scattering Of 1.33 Mev Gamma Rays From Lead, William Jack Merrow

Masters Theses

No abstract provided.

Elastic Scattering Of 1.33 Mev Gamma Rays From Uranium, David Rood Schwandt

Masters Theses

No abstract provided.

Lattice Dynamics And Second-Order Raman Spectrum Of Naf, John R. Hardy, A. M. Karo, I. W. Morrison, C. T. Sennett, J. P. Russell

John R. Hardy Papers

The second-order Raman spectrum of NaF has been measured using an argon laser source. For a light beam incident along the [010] direction, polarized along the [001] direction, and viewed along the [100] direction, the scattered radiation is almost completely polarized. It is shown theoretically that it is possible to account for the polarization and the detailed shape of the observed spectrum within the experimental resolution using a Raman polarizability tensor whose second derivatives with respect to nuclear displacements depend only on the positions of first neighbors in the crystal, provided one uses the phonon frequencies derived from a deformation …

Multiple Charge States, Hyperfine Interactions, And Relaxation Processes Of Fe In 57Co-Doped Mgo, J. Chappert, Richard B. Frankel, A. Misetich, N. A. Blum

Physics

The Mössbauer spectra of cobalt-57-doped magnesium oxide have been studied between 1.3 and 550°K in external magnetic fields of up to 135 kOe for both single-crystal and polycrystalline samples. At room temperature and zero external magnetic field, the velocity spectrum is composed of three single lines, attributed to monovalent, divalent, and trivalent iron. In certain samples, for T2+ line undergoes a transition to a quadrupole doublet with a splitting ΔE_Q=0.30±0.02 mm/sec, while in certain other samples, annealed differently, no doublet is observed down to 1.5°K. The first case is in quantitative agreement with a random-strain model …

A Shock Tube Study Of Recombination In The Lean Hydrogen-Oxygen Reaction Based On The Infrared Emission From Water Vapor, Larry S. Blair

Physics & Astronomy ETDs

ABSTRACT

Recombination in the hydrogen-oxygen reaction has been studied by monitoring the growth of infrared emission at 2.7 microns from water vapor as it is formed behind incident shock waves. Experiments were carried out in gas mixtures with hydrogen-to-oxygen ratios between 1.0 and 0.33 and temperatures between 1435° and 1868°K. Reactants were diluted with 92-98% argon. The validity of the transparent gas approxi­mation (emission intensity proportional to (H20]) and the relationship between emission intensity and temperature were established by cali­bration experiments in which mixtures of water vapor and argon were shock-heated to temperatures between 1328° and 1982°K. Analysis of H20-emission …