skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Influence of the electrode gap separation on the pseudospark-sourced electron beam generation

Journal Article · · Physics of Plasmas
DOI:https://doi.org/10.1063/1.4959175· OSTI ID:22600002
; ; ; ; ;  [1]; ;  [2]
  1. Department of Physics, SUPA, University of Strathclyde, Glasgow, G4 0NG Scotland (United Kingdom)
  2. High Voltage Division, School of Electrical Engineering, Xi'an Jiaotong University, Xi'an 710049 (China)

Pseudospark-sourced electron beam is a self-focused intense electron beam which can propagate without any external focusing magnetic field. This electron beam can drive a beam-wave interaction directly or after being post-accelerated. It is especially suitable for terahertz radiation generation due to the ability of a pseudospark discharge to produce small size in the micron range and very high current density and bright electron beams. In this paper, a single-gap pseudospark discharge chamber has been built and tested with several electrode gap separations to explore the dependence of the pseudospark-sourced electron beam current on the discharge voltage and the electrode gap separation. Experimental results show that the beam pulses have similar pulse width and delay time from the distinct drop of the applied voltage for smaller electrode gap separations but longer delay time for the largest gap separation used in the experiment. It has been found that the electron beam only starts to occur when the charging voltage is above a certain value, which is defined as the starting voltage of the electron beam. The starting voltage is different for different electrode gap separations and decreases with increasing electrode gap separation in our pseudospark discharge configuration. The electron beam current increases with the increasing discharge voltage following two tendencies. Under the same discharge voltage, the configuration with the larger electrode gap separation will generate higher electron beam current. When the discharge voltage is higher than 10 kV, the beam current generated at the electrode gap separation of 17.0 mm, is much higher than that generated at smaller gap separations. The ionization of the neutral gas in the main gap is inferred to contribute more to the current increase with increasing electrode gap separation.

OSTI ID:
22600002
Journal Information:
Physics of Plasmas, Vol. 23, Issue 7; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 1070-664X
Country of Publication:
United States
Language:
English