An experimental investigation of the Buneman instability

The Plasma Betatron, a toroidal turbulent heating device, is modified so that a short (200 nsec duration) electric field pulse (maximum strength 650 V/m) is applied to accelerate electrons to a drift velocity vD much larger than the initial thermal velocity VTH. The device has a major radius of 19 cm and a minor radius of 3 cm, and a plasma having an electron density of 4 x 1016 ~ 1.2 x 1017 m-3 is prepared by rf ionization in a toroidal magnetic field of ~.2 T. A ratio of VD/VTH ~> 5 has been realized which is sufficient for the development of the electron-ion two stream instability. Rapid decay of the plasma current, concurrent turbulent electron heating and an anomalously high electron-ion collision frequency are also observed. However, the Buneman frequency is not observed. Following the collapse of the current, strong oscillations near the ion plasma frequency are detected. Most of the experimental results are in qualitative agreement with recent theoretical predictions.

Name thesis:degree_name

Master of Science (M.Sc.)

Level thesis:degree_level

Masters

Discipline thesis:degree_discipline

Physics

Grantor

University of Saskatchewan

Year dc:date.issued

1981

Author dc:creator

• Paulson, James Daniel

Advisor dc:contributor.advisor

• Hirose, A.

Language dc:language.iso

en_US

Handle dc:identifier.uri

https://hdl.handle.net/10388/etd-06132012-145824

OAI identifier oai:identifier

oai:harvest.usask.ca:10388/etd-06132012-145824