Accession Number : AD0806543

Title :   NOISE CHARACTERISTICS OF CONVERGENT CROSSED-FIELD SPACE-CHARGE FLOWS.

Descriptive Note : Technical rept.,

Corporate Author : MICHIGAN UNIV ANN ARBOR ELECTRON PHYSICS LAB

Personal Author(s) : Lele, S. G.

Report Date : DEC 1966

Pagination or Media Count : 268

Abstract : The purpose of this study is to investigate the noise transport characteristics of space-charge flows in crossed d-c electric and magnetic fields. The theoretical work consists of a Monte Carlo analysis of the noise characteristics of Kino-type electron guns, a parallel plane diode gun and a crossed-field drift space. The experimental studies are concerned with the detection and control of signal (noise) transport along the beams in these guns. An IBM-7090 high speed digital computer is used to simulate random electron emission from the cathode and the subsequent space-charge flows in the gun and drift regions under both short- and open-circuit assumptions. Relevant data for noise parameter calculations are collected during these simulation runs and stored on magnetic tapes. Kinetic noise-voltage and noise-current fluctuations are considered only in the direction of the d-c beam velocity at each point in the beam. A significant change in the values of the noise parameters at a given beam cross section is found to occur in the neighborhood of the hybrid frequency for that region of the beam. Space-charge smoothing is not limited to the potential minimum region but continues for some distance along the beam. An r-f probe technique was used to study signal (noise) transport in crossed-field guns. Self-oscillations were detected in the frequency range of 90-125 MHz and the oscillation frequency was found to be a function of electric and magnetic field strengths and cathode temperature. (Author)

Descriptors :   *SPACE CHARGE), (*ELECTRON GUNS, (*CROSSED FIELD DEVICES, ELECTRONS), MONTE CARLO METHOD, VOLTAGE, DIRECT CURRENT, ELECTRIC FIELDS, MAGNETIC FIELDS, ELECTRON BEAMS, DETECTION, NOISE, SIMULATION, MATHEMATICAL MODELS, POWER SPECTRA, VELOCITY, FREQUENCY.

Subject Categories : Electrical and Electronic Equipment
      Electricity and Magnetism

Distribution Statement : APPROVED FOR PUBLIC RELEASE