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Title: Characterization of multicapillary dielectric cathodes

Abstract

Parameters of the plasma and electron beam produced by a multicapillary cathode in a diode powered by a {approx}200 kV, {approx}300 ns pulse are presented. It was found that the source of electrons is the plasma ejected from the capillaries. Inside the capillaries this plasma obtains electron density and temperature of {approx}8x10{sup 15} cm{sup -3} and {approx}5 eV, respectively. In the vicinity of the cathode, the density and temperature of the plasma electrons were found to be 2x10{sup 14} cm{sup -3} and 4.5 eV, respectively, for electron current density of {approx}40 A/cm{sup 2}. It was shown that the plasma expansion velocity is in the range of (1-2)x10{sup 6} cm/s for current density of >12 A/cm{sup 2}.

Authors:
; ; ; ;  [1]
  1. Physics Department, Technion, 32000 Haifa (Israel)
Publication Date:
OSTI Identifier:
20971894
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 90; Journal Issue: 18; Other Information: DOI: 10.1063/1.2735544; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BEAM-PLASMA SYSTEMS; CAPILLARIES; CATHODES; CURRENT DENSITY; DIELECTRIC MATERIALS; ELECTRON BEAMS; ELECTRON DENSITY; ELECTRON TEMPERATURE; ELECTRONS; EV RANGE 01-10; ION TEMPERATURE; PLASMA; PLASMA DENSITY; PLASMA DIAGNOSTICS; PLASMA EXPANSION; PULSES; THERMIONIC DIODES

Citation Formats

Gleizer, J. Z., Hadas, Y., Yarmolich, D., Felsteiner, J., and Krasik, Ya. E.. Characterization of multicapillary dielectric cathodes. United States: N. p., 2007. Web. doi:10.1063/1.2735544.
Gleizer, J. Z., Hadas, Y., Yarmolich, D., Felsteiner, J., & Krasik, Ya. E.. Characterization of multicapillary dielectric cathodes. United States. doi:10.1063/1.2735544.
Gleizer, J. Z., Hadas, Y., Yarmolich, D., Felsteiner, J., and Krasik, Ya. E.. Mon . "Characterization of multicapillary dielectric cathodes". United States. doi:10.1063/1.2735544.
@article{osti_20971894,
title = {Characterization of multicapillary dielectric cathodes},
author = {Gleizer, J. Z. and Hadas, Y. and Yarmolich, D. and Felsteiner, J. and Krasik, Ya. E.},
abstractNote = {Parameters of the plasma and electron beam produced by a multicapillary cathode in a diode powered by a {approx}200 kV, {approx}300 ns pulse are presented. It was found that the source of electrons is the plasma ejected from the capillaries. Inside the capillaries this plasma obtains electron density and temperature of {approx}8x10{sup 15} cm{sup -3} and {approx}5 eV, respectively. In the vicinity of the cathode, the density and temperature of the plasma electrons were found to be 2x10{sup 14} cm{sup -3} and 4.5 eV, respectively, for electron current density of {approx}40 A/cm{sup 2}. It was shown that the plasma expansion velocity is in the range of (1-2)x10{sup 6} cm/s for current density of >12 A/cm{sup 2}.},
doi = {10.1063/1.2735544},
journal = {Applied Physics Letters},
number = 18,
volume = 90,
place = {United States},
year = {Mon Apr 30 00:00:00 EDT 2007},
month = {Mon Apr 30 00:00:00 EDT 2007}
}
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