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arXiv · 1108.4015

Ultraviolet stimulated electron source for use with low energy plasma instrument calibration

Kevin Henderson·Ron Harper·Herb Funsten·Elizabeth MacDonald
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Abstract

We have developed and demonstrated a versatile, compact electron source that can produce a monoenergetic electron beam up to 50 mm diameter from 0.1 to 30 keV with an energy spread of <10 eV. By illuminating a metal cathode plate with a single near ultraviolet (UV) light emitting diode (LED), a spatially uniform electron beam with 15% variation over 1 cm2 can be generated. A uniform electric field in front of the cathode surface accelerates the electrons into a beam with an angular divergence of <1 degree at 1 keV. The beam intensity can be controlled from 10^9 electrons/cm2s.

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Kevin Henderson, Ron Harper, Herb Funsten, Elizabeth MacDonald. 2011-08-19. Ultraviolet stimulated electron source for use with low energy plasma instrument calibration. https://doi.org/10.1063/1.4732810

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