|
BEACON eSpace at Jet Propulsion Laboratory >
JPL Technical Report Server >
JPL TRS 1992+ >
Please use this identifier to cite or link to this item:
http://hdl.handle.net/2014/41012
|
| Title: | Potential fluctuations and energetic ion production in hollow cathode discharges |
| Authors: | Goebel, Dan M.
Jameson, Kristina K.
Katz, Ira
Mikellides, Ioannis G. |
| Keywords: | keeper
probes
wares |
| Issue Date: | 13-Oct-2007 |
| Publisher: | American Institute of Physics |
| Citation: | Physics of Plasmas 14, 103508 2007 DOI: 10.1063/1.2784460 |
| Abstract: | Ions with energies significantly in excess of the applied discharge voltage have been reported for many years in hollow cathode discharges. Models of dc potential hills downstream of the cathode and instabilities in postulated double layers in the cathode orifice have been proposed to explain this, but have not been substantiated. Measurements of the dc and rf plasma density and potential profiles near the exit of hollow cathodes by miniature fast-scanning probes suggests that turbulent ion acoustic fluctuations and ionization instabilities in the cathode plume significantly increase the energy of the ions that flow from this region. Increases in the discharge current and/or decreases in the cathode gas flow enhance the amplitude of the fluctuations and increase the number and energy of the energetic ions, which increases the erosion rate of the cathode electrodes. The transition from the quiescent "spot mode" to the noisy "plume mode" characteristic of these discharges is found to be a gradual transition of increasing fluctuation amplitudes. |
| URI: | http://hdl.handle.net/2014/41012 |
| Appears in Collections: | JPL TRS 1992+
|
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.
|
