Practical E-Beam Generation of Air Plasma for Airborne Applications

Abstract

The generation and sustainment of air plasma generated by a high-energy electron beam and a sustaining electric field was investigated theoretically and experimentally. Theoretical calculations of power quantify a factor of 2 reduction in power at 60 Torr for a sustaining electric field of 0.4 Td. The reduction in power occurs because the detachment rate of electrons from negative oxygen ions is high and more efficient than generating free electrons via impact ionization. Experimentally, a 100 keV electron beam, operating with a few mA of beam current, ionized air in a 400-liter test cell with pressure ranging from 1 mTorr to 638 Torr. Optical measurements quantified the electron density profile along an RF propagation path. A microwave detection system measured the magnitude and phase of a RF signal at 10 GHz. The relative magnitude and phase of the RF signal quantify the complex wavenumber and permit calculation of the electron density and momentum-transfer collision rate. Measurements in the presence of a sustaining electric field indicated an influence on the electron density. The initial result is encouraging but difficult to interpret due to experimental details.

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Document Details

Document Type
Technical Report
Publication Date
Nov 30, 2009
Accession Number
ADA565343

Entities

People

  • Robert J. Vidmar

Organizations

  • University of Nevada, Reno

Tags

Communities of Interest

  • Advanced Electronics
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Cellular Structures
  • Collisions
  • Detection
  • Detectors
  • Electric Fields
  • Electron Beams
  • Electron Density
  • Electrons
  • Energy
  • Energy Storage
  • Free Electrons
  • Frequency
  • High Energy
  • Ionization
  • Measurement
  • Momentum Transfer
  • Wave Propagation

Fields of Study

  • Physics

Readers

  • Acoustical Oceanography.
  • Plasma Physics.
  • Pulsed Power and Plasma Physics.

Technology Areas

  • Directed Energy
  • Directed Energy - Lasers
  • Microelectronics