Accession Number:

ADA222044

Title:

Plasma Cloaking: Air Chemistry, Broadband Absorption, and Plasma Generation

Descriptive Note:

Final rept. 15 May 1985-14 Feb 1990

Corporate Author:

SRI INTERNATIONAL MENLO PARK CA

Personal Author(s):

Report Date:

1990-02-01

Pagination or Media Count:

85.0

Abstract:

Plasmas with electron number densities from 109 cm -3 to 5 x 1011 cm -3 generated in air or a noble gas constitute tenuous plasmas. If the ambient pressure is near atmospheric, so that the gas density is of the order of 1016 cm -3 to 1019 cm -3, then the plasma is collisional, and the cold collisional dispersion relation predicts electromagnetic characteristics. A plasma generated by an electron beam or by photoionization produces a spatially decreasing electron density. This spatial electron density, approximated as an Epstein profile, results in low backscatter and high attenuation. Bandwidth and attenuation are quantified. An air-chemistry deionization solution is described that estimates plasma lifetime. The lifetime and electron density are sufficient to estimate the power required by a plasma absorber. Plasmas generated in air required in air require a high input power. A plasma generated in a noble gas, seeded with a readily ionized material, and confined by a membrane, requires much less power, and is technically feasible. Keywords Atmospheric plasma, Broadband absorber, Cloaking device, Epstein profile, Noble gases, Plasma generation.

Subject Categories:

  • Plasma Physics and Magnetohydrodynamics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE