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in subjects: "Electrons"

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Diffusion of Slow Electrons in Gases

The properties of electrons in a gas and an external electric field, e.g., agitation velocity, free path, energy lost per collision, and collision cross sections, were determined for electrons of energy less than 2 ev in a large number of gases. The computations were made from previously measured values for Townsend's energy factor or the ratio of electron agitation energy to molecule thermal energy. Results are presented for hydrogen, nitrogen, carbon dioxide, methane, ethylene, cyclopropane, … more

Date: October 24, 1961

Creator: Forester, D. W. & Cochran, L. W.

Item Type: Thesis or Dissertation

Partner: UNT Libraries Government Documents Department

open access

Total hadron cross section, new particles, and muon electron events in e/sup +/e/sup -/ annihilation at SPEAR

The review of total hadron electroproduction cross sections, the new states, and the muon--electron events includes large amount of information on hadron structure, nine states with width ranging from 10's of keV to many MeV, the principal decay modes and quantum numbers of some of the states, and limits on charm particle production. 13 references. (JFP)

Date: January 1, 1976

Creator: Richter, B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Is the two-term expansion valid for highly anisotropic systems. The Townsend ionization coefficient in strong runaway as a test case

The Townsend ionization coefficient in the strong runaway regime is calculated within the framework of the two-term expansion. Results are compared to the 1-D model. General features of the two models are qualitatively similar, but quantitative differences by factors of approx. 2 are observed.

Date: July 15, 1982

Creator: Yu, S. S. & Melendez, R. E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Analysis of valence-electron structures of Y/sub 3/Al/sub 5/O/sub 12/(YAG) and Al/sub 2/O/sub 3/, Cr/sub 2/O/sub 2/ (Ruby), a study of certain properties of these laser materials related to their valence-electron structures

A direct method of determination of the valence-electron structure from its crystal structure has been presented by the writer at XIIth International Congress of Crystallography, at Ottawa, 1981. Here the method is applied to determine the valence-electron structures of Y/sub 3/Al/sub 5/O/sub 12/ (YAG) and Al/sub 2/O/sub 3/, Cr/sub 2/O/sub 3/ (ruby) to see how certain properties of these laser materials are related to their valence-electron structures. The first point observed is the very stron… more

Date: January 1, 1982

Creator: Yu, S. H. & Yu, L. H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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THERMIONIC RESEARCH AND DEVELOPMENT PROGRAM. Quarterly Progress Report No. 3.

No Description Available.

Date: January 1, 1969

Creator: Jacobson, D. L. & Hamerdinger, R. W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Giotto observations of the bow shock at Comet Halley

Preliminary results from the JPA instrument on Giotto indicate that Comet Halley, even on the flanks, has a bow shock which moves backwards and forwards over the spacecraft. To understand the structure properly will require more detailed investigation of the relationships between three particle populations, cometary ions, solar wind ions and electrons.

Date: January 1, 1986

Creator: Formisano, V.; Amata, E.; Wilken, B.; Jockers, K.; Johnstone, A.; Coates, A. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Proposal to assemble a high resolution-electron sensitive-energy flow calorimeter in the NEULAND spectrometer

A ..gamma.. catcher and a liquid scintillation calorimeter module in a simple configuration that is well suited to the investigation of several different neutrino induced processes are described. The variety of neutrino beams now available at Fermilab and synchrotron intensity and energy together with the high resolution calorimeter allow a multiplicity of experiments to be carried out with a single detector configuration.

Date: January 1, 1977

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Data needs for the track structure of alpha particles and electrons in water

We have made calculations of the ionization spectra for alpha particle and electron tracks in water. We have also computed the number of ions created per micrometre of track length, the energy distribution of the secondaries, and the energy expended per ion pair created. Our aim is less toward theoretical derivations than to obtain a numerically accurate description of the track structure at all energies in a form suitable for biomedical applications. 13 references.

Date: January 1, 1983

Creator: Pagnamenta, A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Dose-rate conversion factors for external exposure to photons and electrons

Dose-rate conversion factors for external exposure to photons and electrons have been calculated for approximately 500 radionuclides of potential importance in environmental radiological assessments. The dose-rate factors were obtained using the DOSFACTER computer code. The results given in this report incorporate calculation of electron dose-rate factors for radiosensitive tissues of the skin, improved estimates of organ dose-rate factors for photons, based on organ doses for monoenergetic sou… more

Date: August 1, 1981

Creator: Kocher, David C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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One and two electron integrals over Cartesian Gaussian functions

A formalism is developed which allows overlap, kinetic energy, potential energy and electron repulsion integrals over cartesian Gaussian functions to be expressed in a very compact form involving easily computed auxiliary functions. Similar formulas involving the same auxiliary functions are given for the common charge moments, electric-field operators, and spin-interaction operators. Recursion relations are given for the auxiliary functions which make possible the use of Gaussian functions of … more

Date: January 1, 1976

Creator: McMurchie, L. E. & Davidson, E. R.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Properties of leptons

The properties of the electron, muon, tau, and their neutrinos are reviewed. Three discrepancies in our understanding of those properties are discussed: the lifetime of orthopositronium, the mass spectra of e{sup +}e{sup -} pairs produced in heavy ion collisions, and the 1-charged particle modes problem in tau decays. The review concludes with a discussion of what we need to learn about the tau and the consequent need for a tau-charm factory. 68 refs., 7 figs., 8 tabs.

Date: December 1, 1989

Creator: Perl, Martin L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Excited state electron spin coherence (ESESC) studies of triplet states in molecular solids

The field of coherent spectroscopy of two-level systems is applied to the lowest triplet state of organic molecules. By neglecting the triplet sublevel not coupled by the field, it is possible to describe the remaining two levels with Feynman-Vernon-Hellwarth geometrical representation of a general two-level system. The equations of motion of the pseudomagnetization are derived after transformation to the rotating frame, as are Bloch-type equations which include phenomenological relaxation time… more

Date: February 1, 1978

Creator: Tarrasch, M.E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Measurements of beat wave accelerated electrons in a toroidal plasma

Electrons are accelerated by large amplitude electron plasma waves driven by counter-propagating microwaves with a difference frequency approximately equal to the electron plasma frequency. Energetic electrons are observed only when the phase velocity of the wave is in the range 3v{sub e} < v{sub ph} < 7v{sub e} (v{sub ph} was varied 2v{sub e} < v{sub ph} < 10v{sub e}), where v{sub e} is the electron thermal velocity, (kT{sub e}/m{sub e}){sup {1/2}}. As the phase velocity increases, fewer elect… more

Date: June 1, 1992

Creator: Rogers, J.H. (Princeton Univ., NJ (United States). Plasma Physics Lab.) & Hwang, D.W. (California Univ., Davis, CA (United States). Dept. of Applied Science Lawrence Livermore National Lab., CA (United States))

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Angular distributions of photoelectrons and non-thermal photoions from atoms and molecules. [Review]

During the last ten years, photoelectron angular distributions have been used extensively to study the dynamics of the photoionization process in atoms and molecules. Some major advances in this body of work are reviewed with special emphasis on results emerging since the last Conference on VUV Radiation Physics three years ago. By far the greatest progress has occurred for atoms, where interest is focussed on improving zero-order (Hartree-Slater, Cooper-Zare) understanding of the asymmetry par… more

Date: January 1, 1977

Creator: Dehmer, J. L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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The Specific Heat of Dysprosium Metal Between 0.4 and 4 K

Submitted to Illinois Inst. of Tech., Chicago. A He/sup 3/ cryostat was built to measure the specific heat of rare earth metals which have a component, at low temperatures, attributable to the electrons in the incomplete 4f shell. The specific heat of dysprosium from 0.4 to 4.2 deg K was measured. Pertinent theories about specific heats are outlined. The apparatus included the cryostat, vacuum and He/sup 3/ systems, calorimeter, carbon thermometer, heater, and magnetic thermometer. The experime… more

Date: August 1, 1962

Creator: Guenther, R. A.

Item Type: Thesis or Dissertation

Partner: UNT Libraries Government Documents Department

open access

Very high Mach number shocks: theory

The theory and simulation of collisionless perpendicular supercritical shock structure is reviewed, with major emphasis on recent research results. The primary tool of investigation is the hybrid simulation method, in which the Newtonian orbits of a large number of ion macroparticles are followed numerically, and in which the electrons are treated as a charge neutralizing fluid. The principal results to be presented are (1) electron resistivity is not required to explain the observed quasi-stat… more

Date: January 1, 1986

Creator: Quest, K. B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Contribution of secondary electrons to radiation fields produced by pion beams

In recent years many biological and therapeutic studies have been done with a variety of high-energy particles. Although the theoretical and experimental application of collision cross sections for low-energy particles (less than or equal to 20 MeV) to microsodimetry continues to be a major area of interest, relatively little effort has been devoted to the application of such cross sections to a description of the interaction of high-energy particles in tissue. This article presents an approach… more

Date: January 1, 1982

Creator: Dicello, J.F.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Phase Transformations in Alumina. Technical Report, May to December 1961

e transformation studies showed that synthetic aluminas produced in the laboratory were not transformed to alpha alumina at 400 to 700' deg n the presence of nitric acid and water vapor. Amorphous aluminn produced in the pilot plant was transformed to alpha alumina. This indicated that the amorphous alumina produced in the pilot plant is structurally predisposed to form alpha alumina. Most additives did not appear to have any special effects. Lithium formed zeta alumina, LiAl/sub 5/O/sub 8/. Ph… more

Date: December 1, 1961

Creator: Eding, H J; Huggins, M L & Brown, A G

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Plasma-Induced Conversion of Surface-Adsorbed Hydrocarbons

Experimental results are reported for an electrical device for direct conversion of methane into higher hydrocarbons. A microchannel plate is excited with electrons from a photoemissive source, and electron impact ionization of methane on the inner surfaces of the microchannels creates an ion feedback process. The resulting low-density plasma creates higher hydrocarbons when charged particles impact the surfaces at grazing incidence. The production Of C{sub 2} to C{sub 8}-containing gases was n… more

Date: January 1, 1992

Creator: Sackinger, W. M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Experimental test of resonant absorption theory. Final report, January 1, 1978-December 31, 1979

This experimental research has probed the nature of resonant absorption (RA) of laser light by laser-produced plasmas. The plasmas were created by optical breakdown of a shockfront produced in an electrothermal shock tube. This procedure allows the density structure of the plasma, and in particular, the orientation of the plasma critical-density surface, to be reproducibly formed from one shot to the next. Thus, for the first time, RA has been controllably and reproducibly studied in isolation … more

Date: May 1, 1979

Creator: Yablonovitch, E

Item Type: Report

Partner: UNT Libraries Government Documents Department

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(Ionization in liquids)

This document describes charge transport following ionization of model liquids and how this process may be important in carcinogenesis. 15 refs., 2 figs., 4 tabs. (MHB)

Date: January 1, 1991

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Radiation Shielding Design Considerations for Doublet III

Calculations and measurements were made of the bremsstrahlung (x-ray) doses resulting from runaway electron shots at Doublet III. The analysis considered direct, wall-scattered, and skyshine contributions. Reasonably good agreement was obtained between calculations and measurements. The x-ray dose in the control room was about 1 mR per runaway shot, while that at the north boundary was undetectable, with a calculated value of 0.05 mR per shot. These low doses attest to the adequacy of the 2 ft … more

Date: June 1, 1980

Creator: Engholm, B. A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Counterstreaming solar wind halo electron events on open field lines

Counterstreaming solar wind halo electron events have been identified as a common 1 AU signature of coronal mass ejection events, and have generally been interpreted as indicative of closed magnetic field topologies, i.e., magnetic loops or flux ropes rooted at both ends in the Sun, or detached plasmoids. In this paper we examine the possibility that these events may instead occur preferentially on open field lines, and that counterstreaming results from reflection or injection behind interplan… more

Date: January 1, 1991

Creator: Gosling, J.T.; McComas, D.J. & Phillips, J.L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Direct electron absorption of fast waves on the D3-D tokamak

No Description Available.

Date: June 1, 1992

Creator: Petty, C. C.; Pinsker, R. I.; Chiu, S. C.; deGrassie, J. S.; Lohr, J.; Luce, T. C. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department