Nature of high-energy ions in the cathode plasma jet of a vacuum arc with high rate of current rise
- Electrical Discharge and Plasma Laboratory, Department of Interdisciplinary Studies, Fleischman Faculty of Engineering Tel Aviv University, P. O. B. 39040, Tel Aviv 69978 (Israel)
The production mechanism of extremely high-energy (up to 10 keV) ions observed in vacuum arcs having only a few tens of volts of arc voltage was considered. A model was developed for the plasma acceleration in a high-current ({>=}1 kA) short pulsed (<1 {mu}s) vacuum arc, taking into account the high rate of rise of the spot current (dI/dt>100 MA/s). A system of equations, including equations for the cathode spot and the plasma jet, was solved self-consistently with dI/dt in the range of 0.1-10 GA/s. It was shown that the plasma could be accelerated to the measured energy in the near spot region due to a gas dynamic mechanism and that the ion energy depends on the ratio of the ion flux to the electron flux. This ratio is determined by the cathode erosion rate. The calculated cathode erosion rate varies from 200 to 10 {mu}g/C when the ion energy increases from 0.1 to 10 keV and well agrees with measurements.
- OSTI ID:
- 20634308
- Journal Information:
- Applied Physics Letters, Vol. 85, Issue 14; Other Information: DOI: 10.1063/1.1801171; (c) 2004 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
- Country of Publication:
- United States
- Language:
- English
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