Physics Commons^™

"Invariant Imbedding" And Wave Propagation In Inhomogeneous Media, Crawford J. Maccallum

Physics & Astronomy ETDs

We wish now to address ourselves to that problem which can be described in physical terms as the reflection and transmission of "waves" by and through some sort of "transition region" between two homogeneous media. At this stage we will work strictly within one dimension; later on this severe restriction will be somewhat eased. For simplicity of notation we will for the present give the transition region a finite thickness h; later on we will often allow h to become infinite when the disturbance due to the transition region dies away fast enough with distance.

Long-Range Particles From Nuclear Fission, Ralph A. Nobles

Physics & Astronomy ETDs

This work is concerned with experimental observations of the long-range particles which are occasionally emitted by fissioning nuclei. These particles are known to be principally alpha particles and are of interest because they are associated with the configuration of the nucleus at the crucial time of scission. Observations were made of the energy spectra of long-range particles by means of a thallium-activated multiple CsI crystal scintillator device.

A Calibration Method For Satellite Cerenkov Instrumentals, Robert E. Dekinder Jr.

Physics & Astronomy ETDs

The problem posed for this thesis is one of determining a method of calibrating a photomultiplier tube when it is contained in an orbiting instrumentation package. Since it is planned for the satellite to remain in orbit for about two years, a method to determine drift of the telemetered output versus the selected radiation input would be very desirable. This drift could arise from changes in the power supplied to the system, or by the telemetering or logic circuits changing characteristics from exposure to cosmic radiation. The situation requires that light of constant intensity be produced in the "field of …

The Wavelength Shifting Of Cerenkov Radiation, Philip A. Deutchman

Physics & Astronomy ETDs

The main interest in this paper is to study the effect of the florescent wavelength shifter "POPOP" with respect to Cerenkov radiation and to determine how the efficiency of a Cerenkov counter is affected.

Angular Distribution Of Electrons In Extensive Air Showers, Don D. Laniewski

Physics & Astronomy ETDs

Electrons are the main products of an extensive air shower and comprise approximately 90% of the shower. Since these electrons are the most numerous particles near the axis of a large shower and are not easily detected, extensive air showers are most easily studied by means of the electronic component. Thus, whatever concern there may be about the nucleonic cascade of which the electron is an outgrowth, it is necessary first to understand the development of the electronic component and is lateral and angular distribution. Also, for the correct analysis of any experimental data, it is of particular importance to …

An Analysis Of Bursting Bubbles At Liquid Surfaces, Keith James Gilbert

Physics & Astronomy ETDs

This phenomenon of the spray produced by bursting bubbles at liquid surfaces is certainly familiar to drinkers of carbonated soda pop, champagne and other effervescent liquids. This same phenomenon has been observed at ocean surfaces. Small bubbles, some of which originate at great depths, rise to the surface and break; tiny droplet is thrown upward from most of the imploding bubbles. Some of these droplets may be caught and carried into the atmosphere by winds sweeping along the surface. The droplets evaporate but leave small particles of salt suspended in the air; the particles then serve as condensation nuclei and …

Shock-Tube Determination Of Dissociation Rates Of Oxygen, John P. Rink

Physics & Astronomy ETDs

This study has a two-fold purpose--to demonstrate the feasibility of using x-ray densitometry of shock waves to determine chemical reaction rates and to obtain an accurate, independent measurement of the dissociation rate of oxygen.

The rate of dissociation of oxygen in Xe-O₂ mixtures was measured over a temperature range of 3000°K to 6000°K. An x-ray densitometer was used to measure the density during the dissociation process behind a shock wave. It was possible to match the experimental data with theoretical density profiles over a wide range of compositions and initial conditions.

The agreement between results reported here and previous …

Design Of An Instrument To Detect High Energy Photons At High Altitudes, Donald L. Evans

Physics & Astronomy ETDs

The purpose of this thesis is to design a high altitude instrument which will detect photons with an energy greater than 1 Bev, and which will discriminate between zenith and albedo radiation.

Absorbance Of The Oh Radical In A Specific Wavelength Interval Near 309a, Paul F. Bird

Physics & Astronomy ETDs

The absorbance of the OH radical as a function of optical density was studied by computing the absorbance for an incident radiation in the wavelength interval 3089A-3097A. The absorbance was studied for 3 different temperatures and various values of the parameters specifying the line shapes and magnitude of the spectral absorption coefficient.

Isomerism In Bromine Nuclei, Albert Goodman

Physics & Astronomy ETDs

If the phenomenon of isomerism occurred in bromine nuclei, it would be of great help in elaborating the level schemes of these isotopes. The occurrence of isomerism in the odd isotopes of arsenic and rubidium, the nearest odd-Z neighbors to bromine, suggested similar behavior in bromine odd-Z isotopes. In this investigation, the pulsed-beam method was used to search for isomers. The procedure consisted of pulsing the beam of a Van de Graaff accelerator and counting any resulting activities during the time between beam pulses. After preliminary surveys during which natural bromine was bombarded with neutrons and natural selenium was bombarded …

A Proposal For The Use Of The Method Of Characteristics As A Condition On The Numerical Solutions Of Two-Dimensional Lagrangian Isentropic Flow, Christian D. Anderson

Physics & Astronomy ETDs

The method of characteristics has been widely used in two- dimensional problems (i.e., one spatial dimension and time or two spatial dimensions for the steady state), and it was felt that this method, in all or part, could be applied to time-dependent, two- space hydrodynamics.

In this paper we have done the following:

1. Derived the two-dimensional, time-dependent, nonviscous Lagrangian Equations;

2. Discussed, in general, some aspects of the method of characteristics;

3. Applied the method to our Lagrangian equations; and finally,

4. Proposed a possible application of our results to the numerical solution of the Lagrangian equations.

In …