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The Motion Of A Charged Particle In The Field Of A Magnetic Dipole, E. Royce Fletcher

Physics & Astronomy ETDs

The principal difficulties encountered in attempting to solve the general problem of the motion of a non-relativistic, non-radiating charged particle in a magnetic field which varies position and time, are associated with the induced electric field. That is to say, the time variation of the magnetic field produces an electric field which also acts on the particle. Both these fields must be known as functions of time and position if the equations of motion are to be determined exactly.

The Spectroscopic Constants Of The Ground Electronic State Of Hydrogen Molecular Ion, Bertle Daniel Hansen

Physics & Astronomy ETDs

ABSTRACT

An accurate theoretical determination of certain vibration rotation properties of the hydrogen molecular ion is made. Two different methods of analysis are used in the determination of these properties. First, an energy equation for diatomic molecules is

fitted directly to theoretical vibration and rotation eigenenergies of the ground electronic state of H+2 calculated by J.M. Peek. These eigenenergies include adiabatic corrections determined by w.Kolos. Second, a fixed-nucleus potential for the ground electronic state of H+2, calculated by J. M. Peek which did not include adiabatic corrections, is expanded in a power series in the neighborhood of the equilibrium internuclear …

Pressure And Temperature Dependence Of The Acoustic Velocities In Polymethylmethacrylate, James Russell Asay

Physics & Astronomy ETDs

The acoustic velocities in polymethylmethacrylate have been measured with an ultrasonic pulse echo technique as functions of frequency, temperature and pressure. At atmospheric pressure, data on the velocities and attenuation coefficients were obtained over the range of temperature from 22°c to 75°c and for the frequency range of 6 to 30 MHz. At the temperatures of 25, 40, 55 and 75°c, the pressure dependence of the longitudinal and shear velocity was obtained to 150,000 psi at a frequency of 6 MHz. From the frequency measurements of the velocities, the complex elastic moduli in polyrnethylmethacrylate were calculated at room temperature. The …

Dose And Depth Dose Measurements On The Sixth Gemini Flight, A Comparison With The Gemini-4 Radiation Measurements, Marion F. Schneider

Physics & Astronomy ETDs

Two tissue-equivalent ionization chambers were flown behind 0.4 gram/cm.² and 2.5 grams/cm.² of shielding inside the Gemini-6 spacecraft. The instruments measured the radiation levels resulting from primary cosmic radiation and the trapped particle environment of the earth's Van Allen belts. Each sensor was constructed from a special tissue-equivalent plastic with radiation cross sections that closely match standard muscle tissue for the many complex types and energies of radiation encountered in space. The design of the sensor and logarithmic electrometer preamplifier are described in detail. The calibration and directional sensitivity of the sensors with cobalt-60 and cesium-137 gamma radiation …

Surface Resonances In High Frequency Scattering From A Nearly-Sharp Three Dimensional Well., Jaime Marcelo Wong Luy Tay

Physics & Astronomy ETDs

A computational investigation of the effect of a surface transition region of relative half-width δ on certain surface resonances in high frequencies scattering from a nearly-sharp, three dimensional spherical well is performed by the method of partial wave analysis.

An incident beam of particles, described by a scalar plane wave, interacts with a fixed scattering center represented by a dielectric sphere of index of refraction 1.333, with a very small transition region in the boundary of the well, described by an odd polynomial function of third order. This is the scalar-wave analogue to the more complicated problem of scattering of …

Lattice Dynamics And Second-Order Raman Spectrum Of Csf, John R. Hardy, Arnold Karo

John R. Hardy Papers

Results are presented for a precise calculation, based on the deformation dipole model with short-range repulsive interactions between second-neighbor negative ions, of the normal-mode frequency distribution of CsF. The extreme properties of this crystal are reflected in the unusual appearance of the distribution. From these results, we can also predict the form of the second-order Raman spectrum of CsF for two alternative assumptions regarding the Raman polarizability tensor. Both spectra are unusual in that they consist almost entirely of very sharp, clearly separated lines. Furthermore, the spectra corresponding to these two assumptions are very different and should be easily distinguishable …

Far Infrared Properties Of Lattice Resonant Modes. I. Isotope Shifts, Roger D. Kirby, I.G. Nolt, R.W. Alexander Jr., A.J. Sievers

Roger Kirby Publications

The frequency shift of a lattice resonant mode associated with the isotopic substitution of an impurity ion has been measured for NaCl: Cu⁺, KI: Ag⁺, and KBr: Li⁺. For all three systems, the experimental frequency shifts can be described satisfactorily by an Einstein oscillator representation for the resonant mode with the oscillator mass set equal to the impurity-ion mass. The model of Benedek and Nardelli and also Klein does not account for the experimental results of NaCl: Cu⁺ or KBr: Li⁺. The inclusion of anharmonic forces does improve the agreement between …

Magnetic Hyperfine Structure In 125Te, Richard B. Frankel, J. J. Huntzicker, D. A. Shirley, N. J. Stone

Physics

Mössbauer spectra of ¹²⁵TeFe with improved resolution yield μ(35.5 keV) = +0.60 ± 0.02 nm. The effect of this value on hyperfine spectra of ¹²⁵Te are discussed.

New Superconvergent Dispersion Relations For The Forward Πn Crossing-Even Amplitude, David J. George, Barbara N. Hale, Arnold Tubis

Physics Faculty Research & Creative Works

A Liu-Okubo-type dispersion relation is derived for the crossing-even pion-nucleon forward elastic scattering amplitude T⁽⁺⁾. Two subtractions are made, one at the physical scattering threshold and the other at a previously determined zero of T⁽⁺⁾ on the imaginary axis of the complex ω (pion lab energy) plane. The dispersion relation is well satisfied over the whole allowed range of the Liu-Okubo parameter. Moreover, it is nearly saturated by low-energy scattering for a considerable range of the parameter. It should thus serve as an extremely sensitive test of the low-energy scattering data when such data become more accurately …

Associative Detachment: H+Hˉ→₂*+E, Joseph C.Y. Chen, Jerry Peacher

Physics Faculty Research & Creative Works

The process of associative detachment in the (H,H^-) collision system is investigated at energies below 12 eV. In this energy region, the interaction potential between H and H^- has recently been determined. The energy dependence of the cross section is calculated with explicit allowance for the production of "hot" hydrogen molecules. It is observed that associative detachment provides a possible mechanism for generating an inverted population of the residual molecule such as H₂.

Angular Correlation Study Of The 105 Kev Level In Gd155, John B. Gouvas

Masters Theses

No abstract provided.

Electrical Conductivity Of Potassium Chloride, Robert Fuller, Michael H. Reilly, Charles L. Marquardt, John C. Wells

Robert G. Fuller Publications

The electrical conductivity of potassium chloride is discussed within the framework of a four-defect model of the crystal. The four defects are mobile anion and cation vacancies and immobile divalent cation impurities and divalent cation impurity-cation vacancy complexes. The Teltow formulation of the four-defect mode1 fails to describe precisely the measured electrical conductivity of KCl over the entire intrinsic and extrinsic range.

The Red Leak And Its Effect In Ultraviolet Photometry., Jeffrey David Colvin

Physics & Astronomy ETDs

The red leak in the red 􀀉and of the ultraviolet filter (Corning #9863) of the standard UBV photometric system is investigated. Astronomical photometry is discussed in general, and UBV photometry in particular. The photometric system used in this work is also discussed, including telescope, phototube, filters, and amplifier. The standard filters of the UBV system are used, but the standard phototube of this system is not used. An analytic representation of the red leak magnitude correction is developed.

Sixty-five measurements were made for a wide variety of stars from spectral class B3 to spectral class M2. The red leak correction …

Interaction Potential Between The Ground States Of H And Hˉ, Joseph C.Y. Chen, Jerry Peacher

Physics Faculty Research & Creative Works

An investigation of the interaction potential for H and H^- in both ungerade and gerade modes is carried out by a semiempirical method in which the recently observed isotope effect in dissociative attachment of electrons to hydrogen molecules is used. The interaction obtained is complex, and the imaginary parts of the interaction account for electron emissions during the course of the interaction. A comparison of the present result with other calculations is presented. The isotope effect in dissociative attachment is also discussed. It is shown that the ratios of the survival probabilities alone do not provide an adequate approximation …

A Method For Measuring Magnetization To High Pressures, C. R. Johansen, Mark H. Nelson, J. H. Gardner

Faculty Publications

A partially successful attempt has been made to measure the magnetic moment per unit volume of ferromagnetic materials as a function of pressure to the 100-kbar region. The apparatus, an early version of which has been described previously, consists basically of two opposed Bridgman flat anvils of alumina. One anvil also acts as a dielectric-filled microwave resonant cavity for an x-band spectrometer, allowing electron spin resonance studies to be made to high pressure. The sample to be studied is placed in contact with the anvil-cavity and covered with a pressure-transmitting medium which in turn is encircled by a flat pyrophyllite …

Projected Hartree Product Wavefunctions, Gordon A. Gallup

Gordon Gallup Publications

A method for performing a restricted configuration interaction calculation on atoms or molecules based on the use of Young operators from the symmetric groups is discussed and its relation to some other types of calculations is pointed out. The method in its most general form can be said to be an extension of the independent particle approach which represents the wavefunction in terms of the n best possible one-particle orbitals for the n-particle system. Illustrations are given for the hydrogen molecule, the helium atom, and the allyl radical. ©1968 American Institute of Physics

Mössbauer Effect In 57Fe In Copper And The Spin‐Compensated State, B. B. Schwartz, D. J. Kim, Richard B. Frankel, N. A. Blum

Physics

The results of Mössbauer experiments on dilute Fe in Cu in high external magnetic fields (42–146 kOe) are presented here as evidence for significant destruction of the spin‐compensated state by a magnetic field for which μH₀∼kT_K, where kT_K is on the order of the energy change associated with the formation of the spin‐compensated state.

Magnetic‐Field Dependence Of The Hyperfine Field At Fe In Dilute Fe-Pd Alloys, N. A. Blum, Richard B. Frankel

Physics

No abstract provided.

Electron-Impact Lonization Cross Section In Cesium, Kaare J. Nygaard

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The total ionization due to the passage of an electron beam in cesium vapor has been measured with a Tate and Smith-type apparatus. The retarding potential difference method was used in the electron gun to obtain energy resolution better than 0.1 eV. The density of Cs atoms was determined from the Taylor and Langmuir formula and also measured with a surface-ionization detector. The two methods gave the same density to within ±3% when the apparatus was in thermodynamic equilibrium with the Cs reservoir. The cross section for production of Cs+ has been determined from threshold to 100 eV. For energies …

Nuclear Spin-Lattice Relaxation Measurements By Tone-Burst Modulation, David C. Look, Donald R. Locker

Physics Faculty Publications

No abstract provided.

Dielectric Properties Of Solid Solutions Of Bifeo₃ With Pb(Ti, Zr)O₃ At High Temperature And High Frequency, Robert Travis Smith, Gary D. Achenbach, Robert Gerson, William Joseph James

Physics Faculty Research & Creative Works

Solid solutions of BiFeO₃ with PbTiO₃, PbTi_0.5Zr_0.5O₃, and PbZrO₃ were prepared. The crystallographic data on these solutions, which are basically perovskitic, are given. The dielectric constants of the materials were determined at a frequency of 0.53 GHz and at temperatures up to 800°C. Dielectric Curie points were found in solutions containing up to 90 mole % BiFeO₃. These results leave little doubt that BiFeO₃ is ferroelectric or antiferroelectric. The extrapolated Curie point for BiFeO₃ is above 850°C. BiFeO₃ appears more likely to be ferroelectric than …

The Critical And High‐Temperature Behavior Of A Heisenberg Ferromagnet, Harry A. Brown

Physics Faculty Research & Creative Works

No abstract provided.

Cell Model Of A Fluid. I. Evaluation Of The Partition Function And Series Expansions, Ralph G. Tross, Louis H. Lund

Physics Faculty Research & Creative Works

The partition function of a one-dimensional system of particles with all interactions active is formulated in terms of Ising ferromagnetic spin states. It is shown how the partition function for two- and three-dimensional systems can be obtained from the one-dimensional one by restricting the number of bonds per particle. After writing the partition function in matrix form, the operator of interest is diagonalized and its trace expressed in the form of a convenient infinite series. The series is shown to be absolutely convergent and its analytic properties are briefly investigated. It is then applied to one-, two-, and three-dimensional systems …

The Magnetic Dilution Problem, Harry A. Brown, William F. Parks

Physics Faculty Research & Creative Works

No abstract provided.

The Bethe-Weizsäcker Mass Formula And Lennard-Jones N-N Potentials, James Paul Wesley, Alex E.S. Green

Physics Faculty Research & Creative Works

An elementary derivation of the Bethe-Weizscker semiempirical nuclear mass formula which is in the spirit of current views of nuclear structure, is given. Lennard-Jones potentials are assumed to act between nuclear. Thus, the major interaction between nn, pp, and np pairs is taken of the form —g/r3+h/r4, where r is the separation distance between nuclear, and g and h are constants. An additional "symmetry" interaction of the form s/r3 is assumed for np pairs. Summing the potential energy over all nucleon pairs and using the Fermi statistical estimate of the kinetic energy, the Bethe-Weizscker semiempirical mass formula is obtained directly. …

Cell Model Of A Fluid. Ii. Thermodynamic Properties Of The System, Ralph G. Tross, Louis H. Lund

Physics Faculty Research & Creative Works

In Paper I of this series (preceding paper) the model was formulated mathematically, and the solution derived in the form of an infinite series. The convergence and analyticity of the solution were investigated. It was then applied to one-, two-, and three-dimensional systems with nearest-neighbor interactions, and low-temperature series for these systems were obtained. In the present article the thermodynamics of the model are investigated. The series solution of the partition function derived in Paper I is applied to systems with interaction potentials of increasing complexity. The validity of the model is established by showing that in the appropriate limits …

The Theory And Development Of A Dyeing Machine Employing The Rotary Pendulum, Ashley Paul Smith

Master's Theses

A review of dyeing methods for carpet is made with the objective that the requirements of a new machine could be formulated. The proposal for a new machine is made in the light of the above review using a pendulum as the basic component. A theory is developed for the motion of the pendulum which is mounted on a rotating disc, and the experimental work built on theory is outlined. A prototype machine based on the rotary pendulum mechanism was used to dye impregnate carpet.

The Lifetime And Effective Quenching Cross Section Of The 6²P₃/₂ State Of Thallium, Robert Charles Pickett

Doctoral Dissertations

"The measurement of the lifetime of the metastable 6²P₃/₂ state of thallium is discussed. Measurement of time varying optical absorption by time sampling techniques is explained for the study of the decay of the metastable atom concentration following a pulsed radio frequency discharge. The decay of the thallium radiation from optically allowed states terminating on the metastable state is measured at nine different thallium densities in the afterglow of the discharge. This radiation repopulates the metastable state and is displayed on an oscilloscope. The metastable lifetime is measured as a function of the thallium density at three different r-f power …

An Experimental Determination Of The Homogeneous Nucleation Rate Of Water Vapor In Argon And Helium, Louis Benton Allen

Doctoral Dissertations

"An expansion type cloud chamber was used to measure the nucleation rate of water vapor in an atmosphere of helium and argon. A careful study was made of the thermodynamic characteristics during the expansion so that the nucleation data could be interpreted with reasonable accuracy and consistency. A fine wire thermocouple was used to measure the gas temperature during the course of an isentropic expansion in the dry chamber. When the finite heat capacity of the thermocouple is accounted for, it is found that there is almost perfect agreement with the temperature calculated from the equation of state and the …

Polarization Of Compton-Scattered Gamma Rays, James G. Hudson

Honors Theses

Intermediate energy photons (approximately 0.2 mev. to 10 mev.) interact with matter of low atomic number principally through a process called the Compton effect. This process is an inelastic collision of a photon with a free electron at rest. Using the principles of conservation of energy and conservation of momentum the energy of the scattered photon can be found in terms of the incident photon energy and the angle through which it is scattered. The energy of this scattered photon is then given by E¹=(E_O)/(1+α(1-cos θ)) where E_O is the energy of the incoming photon, …