Production of a highly ionized plasma with low impurity level, with and without magnetic bias fields for magnetic compression experiments
Production of a highly ionized plasma with low impurity level, with and without magnetic bias fields for magnetic compression experiments
For the compression of a cylindrical plasma by fast rising axial magnetic fields, the initial state of this plasma is of critical importance (1). Therefore experiments with a preheating discharge for the production of an initial plasma with known and reproducible properties were started at this labo...
Saved in:
Personal Name(s): | Beerwald, H. |
---|---|
Bogen, P. / El-Khalafawy, T. / Fay, H. / Hintz, E. / Kever, H. | |
Contributing Institute: |
Publikationen vor 2000; PRE-2000; Retrocat |
Imprint: |
Jülich
Kernforschungsanlage Jülich Zentralbibliothek, Verlag
1961
|
Physical Description: |
13 p |
Document Type: |
Report Book |
Research Program: |
ohne Topic |
Series Title: |
Berichte der Kernforschungsanlage Jülich
19 |
Link: |
OpenAccess OpenAccess |
Publikationsportal JuSER |
For the compression of a cylindrical plasma by fast rising axial magnetic fields, the initial state of this plasma is of critical importance (1). Therefore experiments with a preheating discharge for the production of an initial plasma with known and reproducible properties were started at this laboratory simultaneously with the first experiments on the compression of a weakly preionized deuterium gas.An electrodeless ring discharge was chosen. The absence of electrodes makes a high degree of purity of the plasma possible. Kolb's experience with a preheating discharge for magnetic com-pression experiments (2) confirmed this conception and gave further impulse to this work. Early experiments were made with a RF-transmitter as current generator, in pulsed as weIl as in stationary operation. Dueto the low inductance of the compression coil considerable difficulties are met in coupling the RF power to the discharge. The maximum available power is limited to some hundred kilowatts. By discharging a low inductance condenser on the compression coil a damped RF pulse with apower of 100 M Watt is easily obtained. To avoid prefiring of the main condenser bank, the voltage of the coil must be lirnited. With the spark gaps used at this laboratory the maximum permissible voltage at the coil was about 5 kV. This voltage, however, is sufficient to start an electrodeless ring discharge in hydrogen. Investigations on this electrodeless ring discharge were made with and without a steady magnetic bias field in a wide pressure range. Preliminary results, concerning the breakdown of the gas, the formation of a highly ionized plasma, and the subsequent decay of the plasma dtie to end losses and recombination are reported in this paper. |