EXPERIMENTS ON RESISTIVE INSTABILITIES IN A TOROIDAL PLASMA
Abstract
Visual observations made on a pulsed toroidal plasma indicate that the current carrying plasma sheet breaks up into filaments parallel to the direction of the current and perpendicular to the direction of the magnetic field. This process involves the annihilation and fusion of initially opposite magnetic flux lines and leads to a final configuration which corresponds to a lower energy state. Such a state, however, would not be accessible in the absence of dissipation since its attainment requires slippage of the plasma across magnetic flux lines. The operating mechanism must then be associated with a resistive instability of the type first predicted by Furth, Kileen, and Rosenbluth and also by Coppi, Greene and Johnson in Physics of Fluids, Volume 6, 1963. Observations of resistive instabilities under laboratory conditions is of particular interest because these modes are held responsible for many astrophysical and geophysical phenomena such as solar flares and auroras as well as anomalous diffusion rates in fusion devices. The experimental setup consists of a plasma filled ring-shaped container of rectangular cross section, where a discharge is induced by means of an iron cored transformer. The time development of the current distribution in the plasma is determined with the help of a combination of magnetic probes and an S. T. L. Image Converter Camera. Optical spectroscopy is used to calculate the temporal variation of electron number density and temperature.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1967
- Accession Number
- AD0671901
Entities
People
- Kenneth D. Stuart
Organizations
- New York University Tandon School of Engineering