PRODUCTION OF A HIGHLY IONIZED DEUTERIUM PLASMA, OF LOW IMPURITY LEVEL, WITH AND WITHOUT MAGNETIC BIAS FIELDS, FOR MAGNETIC COMPRESSION EXPERIMENTS

Journal Article · Mon Jan 01 04:00:00 EST 1962 · Nucl. Fusion, Suppl.

OSTI ID:4726491

Beerwald, H; Bogen, P; El-Khalafawy, T; Fay, H; Hintz, E; Kever, H

Magnetic compression experiments require a well defined, highly ionized initial plasma. Otherwise main effects occur during the second compression half- cycle in a plasma of comparatively high impurity, and under rather uncontrolled conditions. Investigations have been made on the production of plasma by a pulsed, rapidly oscillating electrodeless ring discharge in RF-preionized gas, and within a straight magnetic compression coil. The amount of trapped internal magnetic field is controlled by an initial axial magnetic bias field. The breakdown mechanism can be theoretically and experimentally shown to depend on the direction and strength of the bias field with respect to the pulsed field, and the initial electron density. Ionization growth has been determined by microwave techniques. The results explain typical phenomena of non-preheated compression experimerts. Full ionization in deuterium at electron temperatures around 2 ev is reached. It is observed that heating is due to interdiffusion of magnetic fields of opposite polarity. The plasma has very low impurity content and reaches both thermal equilibrium and a homogeneous density distribution at the end of the preheating pulse. Electron densities are measured by Stark broadening of H/sub BETA . The amplitude of trapped magnetic field can be varied from 0 to 3000 G. The measured field distribution is homogeneous at the end of the pulse. The method produces a fully ionized clean plasma with known and uniform initial parameters such as temperature, density, and internal magnetic field, which can be varied in a reproducible way. (auth)

• Research Organization: Institut fur Plasmaphysik der Kernforschungsanlage, Julich, Ger.
• NSA Number: NSA-17-009739
• OSTI ID: 4726491
• Journal Information: Nucl. Fusion, Suppl., Journal Name: Nucl. Fusion, Suppl.
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

COILS
CONFIGURATION
CONFINEMENT
CONTROL
DENSITY
DEUTERIUM
DIFFUSION
DISTRIBUTION
ELECTRIC DISCHARGES
ELECTRIC FIELDS
ELECTRONS
GASES
HEATING
HOMOGENEOUS REACTORS
HYDROGEN
IMPURITIES
IONIZATION
MAGNETIC COMPRESSION
MAGNETIC FIELDS
MAGNETIC MIRRORS
MEASURED VALUES
MICROWAVES
OSCILLATIONS
PHYSICS
PLASMA
PRESSURE
PRODUCTION
PULSES
RADIO WAVES
SPECTRAL SHIFT
STABILITY
TEMPERATURE
THERMODYNAMICS
TORUS