Accession Number : AD0467862

Title :   HIGH VELOCITY ELECTRON STREAMS RESEARCH.

Descriptive Note : Final rept. 1 Jul 61-15 Jun 65,

Corporate Author : NORTH CAROLINA STATE UNIV AT RALEIGH DEPT OF PHYSICS

Personal Author(s) : Bennett, Willard H. ; Roberts, Albert S., Jr. ; Cox, James L., Jr. ; Beard, Sam G., Jr.

Report Date : 01 JUL 1965

Pagination or Media Count : 85

Abstract : In order to study the stability of intense narrow beams in gases, it is deemed essential to develop methods for producing stable, selffocusing beams which can then be projected into ionized or ionizable gases for study. A hollow cathode arc has been developed as a source of electrons instead of one of the more usually used types of cathodes in order to avoid the disruptive effects upon beam stability resulting from cathode flicker and other irregularities in cathode emissivity caused by back-bombardment by ions. Calculations were made to determine the degree of space charge neutralization required before magnetic self-focusing would be adequate to produce stable steadily running beams. A modification of the duoplasmatron was developed using the hollow cathode arc as electron source. A deep, watercooled probe was developed for use in measuring beam profiles of the intense beams while suppressing secondary currents in the probe. The methods adopted for the formation of the intense beams were expected to give excellent ion trapping and to give good space charge neutralization with the result that stable magnetically self-focusing beams would form. Measurements of beam profile showed that sufficiently good bean symmetry was obtained for the beams to become self-focusing provided the space charge is neutralized. (Author)

Descriptors :   (*ELECTRON BEAMS, SCIENTIFIC RESEARCH), ELECTRIC ARCS, ELECTRIC DISCHARGES, PLASMA MEDIUM, VELOCITY, ELECTROSTATIC FIELDS, FOCUSING, DESIGN, MAGNETIC FIELDS, EQUATIONS, ORGIN, THERMIONIC EMISSION, VACUUM, COILS, EXPERIMENTAL DATA, ANODES(ELECTRON TUBES), CATHODES(ELECTRON TUBES).

Distribution Statement : APPROVED FOR PUBLIC RELEASE