A Method for Estimating Atmospheric Noise Amplitudes and Phase Errors in Quenched High-Q Receiving Circuits

A Method for Estimating Atmospheric Noise Amplitudes and Phase Errors in Quenched High-Q Receiving Circuits
Author: E. A. Lewis
Publisher:
Total Pages: 50
Release: 1965
Genre: Atmospheric electricity
ISBN:

Very narrow-band quenched filters used for studying VLF radio signals differ from conventional narrow-band circuits in that both signal and atmospheric noise impulses cause only brief quasi-sinusoidal outputs instead of a prolonged ringing. The random overlapping of these short noise and signal bursts can cause errors in phase measurements. It is shown that the distribution of phase errors can be calculated from the amplitude distribution of the output noise envelope. The properties of the phase distribution are discussed in detail, the computation required in the general case is illustrated by means of a numerical example. A simple 'time-sequential' method for experimentally obtaining typical amplitude distributions is suggested. (Author).

Effects of Experimental Parameters on Thermoluminescence of a Type II-a Diamond

Effects of Experimental Parameters on Thermoluminescence of a Type II-a Diamond
Author: Albert D. Johnson
Publisher:
Total Pages: 42
Release: 1965
Genre: Crystals
ISBN:

Thermoluminescence provides a method for studying properties of those crystalline imperfections which behave as electron traps and recombination centers in wide bandgap materials. This approach, however, has been used relatively little, possibly due to the fact that the shapes and intensities of thermoluminescent glow curves are functions of several experimental parameters and are often complicated by the overlapping of a number of individual glow peaks. In the present work, experimental parameters were isolated and some of their effects on thermoluminescent glow curves were analyzed. This yielded information on activation energies associated with trapping levels, the nature of the kinetics involved in electron transitions, and electron retrapping. A Type II-a diamond, which has a wide distribution of thermoluminescent glow peaks, was used in this work. (Author).

A Discussion of the Wheeler-Feynman Absorber Theory of Radiation

A Discussion of the Wheeler-Feynman Absorber Theory of Radiation
Author: Ronald G. Newburgh
Publisher:
Total Pages: 34
Release: 1965
Genre: Absorption
ISBN:

The Wheeler-Feynman absorber theory of radiation is reviewed. A proof is offered to show that a sum of advanced and retarded effects from the absorber can provide the origin of radiative reaction. This proof is different from and perhaps simpler than that of Wheeler and Feynman. From arguments of momentum and energy conservation the necessity of the absorber for the emission of radiation is demonstrated for three cases. (Author).

The Theoretical and Numerical Determination of the Radar Cross Section of a Finite Cone

The Theoretical and Numerical Determination of the Radar Cross Section of a Finite Cone
Author: F. V. Schultz
Publisher:
Total Pages: 14
Release: 1965
Genre: Boundary value problems
ISBN:

In this work, rigorous electromagnetic theory is used to determine the nose-on radar cross section of a perfectly conducting cone of finite height. The end cap of the cone is assumed to be a segment of a s spherical surface with center at the apex of the cone. Numerical results have been obtained for a cone having a total apex angle of 30 degrees and for values of [kappa alpha] ranging from 0.0259 to 5.18, where [kappa]=2 [pi]/[lambda] and [alpha] is the radius of the base of the cone. Siegel's Rayleigh method and by using Keller's modified geometrical optics as well as with experimental results obtained by Keys. The comparisons are instructive below [kappa alpha] = 3.2, the apparent upper limit of validity of the present results -- p.[3].

A Study of Band Edge Distortion in Heavily Doped Germanium

A Study of Band Edge Distortion in Heavily Doped Germanium
Author: Freeman D. Shepherd (Jr.)
Publisher:
Total Pages: 98
Release: 1965
Genre: Energy-band theory of solids
ISBN:

Details of the energy band structure of degenerate n-type germanium were determined by analysis of fine structure in the 4.2K volt-ampere characteristic of germanium tunnel diodes. No shift in the relative energy of the conduction band minima was observed. The band edge is found to be exponentially distributed with 1/e energies of the order of 10 MeV. There appears to be an ordering mechanism among the group V impurity atoms used as substrate dopants. (Author).