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Metrology--An Experiment Where Industry And Education Meet, R. B. Hastings

Journal of the Minnesota Academy of Science

This paper describes a project in which students worked in close cooperation with both the physics department of Macalester College and the gage block laboratory of the Continental Machine Company, manufacturers of ,precision gage blocks. Brief descriptions, including drawings, are given of both the interferometer and the constant temperature laboratory in which all measurements were taken. This constant temperature laboratory is set with precision at those two temperatures between which the average coefficient of linear expansion of a gage block is to be determined. Many such readings were taken and computations of the coefficient of expansion were made. Comparison of …

Spectrographic Study Of The Afterglow Of Mercury, Edward E. Stepp, Richard A. Anderson

Physics Faculty Research & Creative Works

The short duration afterglow of 14 Hg lines was examined, at temperatures of 150°, 200°, 250°, and 300°F, in a cell that had been excited by an rf source. All of the lines exhibited a smooth exponential decay at the lowest temperature. At some temperature above 150°F, however, all of the lines, except the 2537- and 4079- Å lines, exhibited an enhancement of intensity in the time region between 50 and 100 µsec. At the highest temperature all of the lines originating from levels at an energy of 8.84 eV or above, except those originating from the 6¹D …

Equation Of State Of Nacl And Its Use As A Pressure Gauge In High-Pressure Research, Daniel L. Decker

Faculty Publications

The pressure as a function of lattice parameter and temperature has been calculated for NaCl over a pressure range of 0 to 500 kbar for temperatures between 0degrees and 1500degrees C. The calculation used the Mie-Gruneisen equation of state with Born-Mayer type repulsion terms between first and second nearest neighbors. The Gruneisen constant was expanded about its value at room temperature and atmospheric pressure; the first coefficient in the expansion being evaluated by forcing the calculated thermal expansion at atmospheric pressure to fit the experimental results of Enck. The two empirical parameters in the repulsion terms were evaluated using the …

New Autoionizing Levels In Helium, M. Eugene Rudd

M. Eugene Rudd Publications

We recently reported the excitation of autoionizing states in helium by positive-ion bombardment and their subsequent observation as fine structure in the energy spectrum of the emitted electrons. With somewhat increased resolution we have now observed additional levels in helium including parts of two series not previously reported.

Physics-Mathematics Building At Kansas State University, Robert Katz

Robert Katz Publications

A building of about 134 000-sq ft area, containing research rooms, shops, store rooms, three lecture halls, classroom, and offices, for the Departments of Physics and of Mathematics has been completed at Kansas State University. Details concerning the construction, the provision of laboratory facilities, and special features of the building are given, as are floor plans and statements of costs involved.

Fock's Representation For Molecular Orbitals, Tai-Ichi Shibuya

University of the Pacific Theses and Dissertations

V. Fock studied the hydrogen atom problem in momentum space by projecting the space onto a 4-dimensional hyper-sphere. He found that as a consequence of the symmetry of the problem in this space the eigen-functions are the R₄ spherical harmonics and that the eigenvalues are determined only by the principal quantum number n. In this chapter we note that if his method is applied to the 2-dimensional Kepler problem in momentum space, the eigenfunctions are the R₃ spherical harmonics, Y_1m, and the eigenvalues are determined only by the quantum number 1. These facts enable one to …

An Investigation Of Current Induced Mass Migration In Solid Metals, Steven Mitchell Kovel

Doctoral Dissertations

"In this investigation of current induced mass transport, the general phenomenological equations will be considered first so as to present a picture of the experimental situation. The theoretical computations are then divided into four sections: (1) the determination of the force on a defect due to electron scattering, (2) a discussion of how the force on the defect might be shared by the surrounding ions, (3) how an external force affects the diffusion frequency of an ion, and (4) what the rate of mass transport is under the influence of an electric field. So as to simplify the discussion and …

A Solution To Einstein's Gravitational Field Equation For A Spherically Symmetrical Static Perfect Fluid, Lionel Donnell Hewett

Doctoral Dissertations

"Given spherical symmetry, Einstein's gravitational field equations are reduced to a single, second order, linear, homogeneous differential equation. The solution of this equation for a homogeneous sphere is identical with Schwarzschild's solution...Values of relative density, interior mass, relative pressure, relative and absolute temperature are obtained as functions of radius, r, and are compared with corresponding values for the homogeneous sphere, and for a model sun"--Abstract, page v.

A Measurement Of Dead Space And Its Effect On The Homogeneous Nucleation Rate Of Water Vapor In Helium, Michael A. Grayson

Masters Theses

"The existence of a "dead space" surrounding each nucleated water droplet is demonstrated and measurements of its rate of development are made. The effects of this "dead space" are considered to be due to both the removal of vapor from the helium-water vapor mixture and the evolution of heat about the drop due to its growth. The results confirm the usefulness of the concept of a "dead space" and provide a means for its measurement with respect to time. Recommendations for further study and a method of correcting for dead space effects is given"--page [i].

Geophysical Institute Annual Report 1964-65, University Of Alaska Fairbanks. Geophysical Institute

GI Reports

The 1964–65 Geophysical Institute Annual Report presents an overview of the year’s scientific research achievements across the Institute’s disciplines, alongside operational summaries covering finances, administrative changes, and other key activities.

Pair Distribution For A Cell-Model Liquid, James M. Phillips

Doctoral Dissertations

"The pair distribution function for a cell-model liquid has been derived by Lund in the form of an integral equation which depends upon the cell-center distribution function and the cell model. From this integral equation an approximate integral equation is obtained by substituting a function, which is linearly dependent upon the molecular pair distribution function and a variable parameter for the cell-center distribution function. This approximate integral equation is solved for the molecular pair distribution and the variable parameter is shown to depend upon the difference between temperature and the critical temperature. Although the exact numerical solution of the molecular …

A Study Of Near Surface Elastic-Anelastic Layers, Charles Allen Aldrich

Doctoral Dissertations

"Wave propagation through layered media is of importance in many disciplines. The near surface layers are of special significance, in that most measurements of waves are made within these layers. The purpose of this investigation was to formulate mathematical models with which to analyze the effects of near surface layering"--Introduction, page 1.

Decay Of Certain Mercury Lines In Argon, Thallium, And Pure Mercury Atmospheres, Edward E. Stepp

Doctoral Dissertations

"Organization of thesis and Hg-A study, The time decay of the intensity of selected mercury lines was examined under three different conditions, Each section of this thesis i s divided into three parts corresponding to these three different conditions, In each section part A concerns the decay of intensity of the 2537, 4079, 4360, and 5462 A mercury lines, following the excitation of the states from which they originate by an Hg-A de discharge, Part B concerns the decay of intensity of 14 mercury lines following the excitation of the originating state of these lines by an intense r-f discharge …

Angular Distributions Of Conversion Electrons From Oriented Ce137M Nuclei, Richard B. Frankel, D. A. Shirley, N. J. Stone

Physics

The angular distributions of K- and of (L+M)-conversion electrons from oriented Ce^137m nuclei were observed. Precise simultaneous intensity measurements of conversion electrons and γ rays from the same sample provided an accurate, direct determination of the particle parameters b₂ associated with the 255-keV isomeric transition in Ce¹³⁷. The K-electron result, b₂=1.061 (18), is in excellent agreement with a theoretical prediction based on a "point nucleus" model. Techniques and parameters in this experiment, the first of its kind, are discussed. A more careful determination of the temperature dependence of …

Observation Of Autoionization Levels In He By Positive Ion Bombardment, M. Eugene Rudd

M. Eugene Rudd Publications

Certain highly excited energy levels in helium have been observed optically and by inelastic electron scattering, and have been calculated theoretically. Reported here is the observation of these levels by the measurement of the energy spectrum of electrons emitted after bombardment with protons and hydrogen molecular ions. Some of the states show up clearly by this method which are weak or absent in the other techniques. Berry has previously observed autoionization of helium by this method, but his measurements lacked the resolution necessary to identify the states.

Investigations Of Neutron Collimators And Detector Systems Used In A Neutron-Capture Internal-Conversion Apparatus, William Charles Johnston

Masters Theses

Preface

During the past six decades considerable effort has been devoted to investigating and explaining the phenomena associated with the atomic nucleus. However, many important features of the nucleus still are not understood. Among these are such fundamental aspects as the structural composition of the nucleus, the nature of the forces between nucleons, and several of the basic processes that occur among the nuclear constituents. The goal of nuclear physics is to construct a unified theory which is able to explain all nuclear phenomena.

The experimentalist contributes toward this objective by gathering and classifying extensive amounts of experimental data in …

The Atmospheric Neutron Spectrum At High Altitudes, Michael Sydor

Physics & Astronomy ETDs

A measurement of neutron flux in the range 30 -130 Mev at altitudes of 10, 670 feet and 100,000 feet was performed with a directionally sensitive proton recoil detector. The detector consisted of two counters of scintillator plastic which measured dE/dx and energy of proton recoils originating in a third plastic scintillator. Charged particles were eliminated by a guard counter. Energy calibration was performed with charged cosmic ray particles; efficiency and angular sensitivity were calculated. The angular response was checked at 10,670 feet, where a reasonable angular distribution of cosmic ray neutrons could be assumed.

Four balloon flights to 100,000 …

Phase-Space Occupation Of Electron, Proton, And Photon Beams, Robert Katz, Basil Curnutte Jr.

Robert Katz Publications

The intensities of known electron, proton, and photon beams are compared to the intensity of a saturated beam of fermions, providing direct experimental evidence for the boson nature of photons.

A Ti-Hg Collision Cross Section, Edward E. Stepp, Richard A. Anderson

Physics Faculty Research & Creative Works

The lifetime of the 6³P₁ state of Hg was observed as a function of Tl density at two different Hg pressures. From these data it appears that at high Tl densities the lifetime of the 6³P₁ state of Hg is controlled by collisions with Tl atoms. Using this assumption and simple gas kinetic theory, a cross section for these collisions was calculated.

Angular Correlation Of Co60, Henry Kuhlman

Masters Theses

Chapter I

Introduction

The probability that a radioactive nucleus will emit a gama ray may depend on the angle between the nuclear spin axis and the direction of emission. The radiation pattern of a sample of randomly oriented nuclei is isotropic. An anisotropic pattern may be observed if the nuclear spin axes are aligned.

Stabilization Of A Balloon-Borne Package, Gary W. Tomlinson

Physics & Astronomy ETDs

It is desirable in certain applications of balloon-borne systems to stabilize the apparatus against rotation about the vertical axis and against tilting. The method of stabilization which will be discussed in this paper involves the use of a set of three gyroscopes which provide a reaction to any torques which would tend to rotate or tilt the package. A model was constructed which demonstrates the feasibility of this method. If the system is to be used for some type of astronomical measurement it may also be desirable to scan a portion of the sky at a constant rate. A method …

Force-On-The-Wall Calculations For One-Dimensional Dense Gases With Intermolecular Potentials., Thomas Daniel Butler

Physics & Astronomy ETDs

The theoretical study of dense gases with strong intermolecular forces is impeded by lack of sufficient experimental which to compare predictions of the properties. High speed computers can supply this information by calculating the detailed dynamics of molecular assemblages, thereby taking the place of an actual physical experiment. This information supplied by the computers not only can test the validity of existing theories, but also it can indicate directions for possible im­provement in the theoretical approximations.

In order to show the adaptability of computers to this task, this thesis deals with the theoretical and computer-experimental study of the force exerted …

A Measurement Of The Spin Relaxation Time Of Optically Pumped Rubidium Vapor, Robert Oliver Breault

Masters Theses

Chapter I

The Problem and Atomic Energy Levels

In 1949 Francis Bitter proposed a method for optcally detecting radio frequency resonance. That same year Alfred Kastler, Fcole Normale Superiéure, Paris, France, introduced a technique, which he called "Optical Pumping", of concentrating atoms in some of the Zeeman sublevels of one of the hyperfine state levels of the ground state. These two experiments are the basis of research involving optical methods of atomic orientation and of magnetic resonance.

The Diffraction Of Polarized Light By A Conducting Straight Edge In The Geometrical Shadow, Richard W. Morris

Physics & Astronomy ETDs

Theory predicts that the diffraction pattern of a conduction straight edge will show deviations from the diffraction pattern of a non-conductor, and further, that these deviations will depend upon the polarization of the incident light. In this experiment the diffraction of polarized, coherent light from a monochromatic source by a metallic straight edge was studied in a region near the edge of the geometrical shadow. Two orientations of the polarization were used: one with the E vector of the polarized light parallel to the diffracting edge, and the other with the E vector perpendicular to the diffracting edge. Three different …

Determination Of The Orientation Of Air-Borne Instrumentation, David G. Miller

Physics & Astronomy ETDs

Air-borne devices have been used as a means of observation and collection of information in meteorology and atmospheric physics for many years. Only in recent years, however, has the increasing use of such devices been made for astronomical observations. A balloon-borne telescope at 80,000 to 100,000 feet, for example, has many advantages: the distortion, absorption and scattering of light by the atmosphere and the dependence on weather conditions, which plagues earthbound observations, are essentially eliminated. It seems apparent that astronomical observation will eventually be able to be made only by air­borne or satellite observatories. The decline in usefulness of the …

Single Crystals Of "Globular Molecules" From The Melt, Charles A. Aeby

Physics & Astronomy ETDs

This thesis is an investigation of the possibility of growing single crystals of dl-camphene, d-camphor, and cyclohexanol. These are organic compounds, characterized by "globular molecules", which form plastic crystals immediately below their melting point. Single crystals were desired in order to study, by ultra-sound techniques, properties pertinent to the evaluation of the elastic constants of these crystals. Primary emphasis was placed on growing crystals of dl-camphene, since it is conveniently handled at room temperatures.

Methods of growth from the melt were chosen because of the relatively fast growth rates, compared to vapor or solution techniques. Secondary considerations were simplicity of …

Phase Changes In Solid Cyclohexanol, William T. Griffith

Physics & Astronomy ETDs

Cyclohexanol is one of a group of organic compounds which exist in a “plastic crystal" solid phase, which is intermediate in its properties between the liquid phase and the solid phases stable at lower temperatures. It has been well established that the odd properties of the plastic crystal phase are due to the relatively unhindered rotation of the molecules about their lattice positions. At temperatures often considerably below the freezing point, these compounds undergo a solid-solid phase transformation in which this rotational freedom is lost. The heats and entropies of transformation at this lower transition point are generally larger than …

Large Angle Scattering Of Polarized Light By A Straight Edge, Theodore S. Fahlen

Physics & Astronomy ETDs

The purpose of this experiment was to observe the light diffracted into the geometrical shadow of a sharp and a blunt metallic straight edge using a polarized, very intense, highly coherent light source. The light source used was a ruby laser, and a Nicol prism was used to linearly polarize the laser light. Two polarizations of the laser beam were used: One with the E vector of the incident beam oriented parallel to the edge of the straight edge, and the other with the E vector oriented perpendicular to the edge. One photomultiplier tube was used to monitor the pulsed …

Variations In The Dielectric Constants Of Camphor And Camphene Under Pressure, Donald R. Wheeler

Physics & Astronomy ETDs

Camphor and camphene are two of a group of substances known as plastic solids. The plastic solids are all characterized by the ease with which they can be deformed. It has been suggested that this property is a result of a great number of mobile vacancies in the crystal lattice. Nabarro and Herring explain the "creep", characteristic of metals, in this way.

The Nuclear-Active Component Of Extensive Air Showers, E. Royce Fletcher

Physics & Astronomy ETDs

In 1900 Wilson (1900; 1901a; 1901b) in England and Elster and Geitel (1900) in Germany began a series of experiments which were ultimately to lead to the discovery of cosmic rays. Using an electroscope mounted in a grounded metal box, they were able to show that the air in a closed vessel has a slight residual conductivity. After careful experiments had eliminated insulator leakage and charged dust particles as possible sources of the observed current, Wilson speculated that the ionization might be due to the presence of some very penetrating radiation coming from outside the atmosphere. Unfortunately, however, he abandoned …