Beam-Plasma Discharge: Buildup of Oscillations

Journal Article · Sun Dec 01 04:00:00 EST 1963 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.1729220· OSTI ID:4138646

Getty, W. D.; Smullin, L. D.

Plasma electron heating was accomplished by exciting plasma oscillations with a pulsed, 10-kV, 1-A electron beam drifting in a longitudinal magnetic field of 100 to 1000 Oe. The oscillatory energy gained by plasma electrons leads to an increase in their density and mean kinetic energy. The resulting plasma, which is called the ``beam-plasma discharge,'' is an rf discharge in which a beam-plasma interaction generates the rf fields. At the beginning of a beam pulse, beam electrons generate a plasma by ionization of the background gas. Within a few microseconds excited plasma electrons become the dominant ionization source. This paper describes the transient rf oscillations that appear in the first few microseconds of the beam pulse. Finally, from a detailed study of this transient it was concluded that a nonconvective instability initiates the oscillations, which first appear at the electron cyclotron frequency, and that a convective instability at the plasma frequency generates the oscillations that sustain the discharge.

• Research Organization: Massachusetts Inst. of Tech., Cambridge
• Sponsoring Organization: USDOE
• NSA Number: NSA-18-002997
• OSTI ID: 4138646
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 12 Vol. 34; ISSN JAPIAU; ISSN 0021-8979
• Publisher: American Institute of Physics (AIP)
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

CURRENTS
CYCLOTRONS
ELECTRIC DISCHARGES
ELECTRIC POTENTIAL
ELECTRON BEAMS
ELECTRONS
ENERGY
EXCITATION
FREQUENCY
GASES
HEATING
IONIZATION
MAGNETIC FIELDS
MOTION
OSCILLATIONS
PHYSICS
PLASMA
PULSES
RADIO WAVES
STABILITY