Accession Number : AD0667525

Title :   EFFECT OF MOLECULAR CONTAMINANTS ON RF-INDUCED PLASMA SHIELD PROPAGATION.

Descriptive Note : Final rept. 15 Oct 64-15 Oct 67,

Corporate Author : GENERAL ELECTRIC CO PHILADELPHIA PA MISSILE AND SPACE DIV

Personal Author(s) : Bethke,G. W.

Report Date : 09 JAN 1968

Pagination or Media Count : 55

Abstract : It was observed that microwave irradiation of localized weak ionization in heavy rare gases (Xe, Kr, and Ar) and in molecular gases (air, N2, O2, NO, CO2, and SF6) can cause an ionization wave to form and propagate towards the rf source. This ionization wave is preceded by an electron precursor, with the electron density at the ionization wave front increasing very rapidly to a maximum followed by a relatively slow plasma decay. At rf power levels well below normal breakdown the ionization wave will form and then propagate at velocities from about 2000 to about 10 to the 7th power cm/second. In rare gases, discontinuous changes of ionization wave velocities with changes in rf power and gas pressure indicate the existence of three different velocity-controlling mechanisms in the rare gas pressure and rf power ranges investigated. These multiple mechanisms for ionization wave formation and propagation in rare gases are discussed. None of the molecular gas ionization waves studied showed such evidence for velocity-controlling multiple mechanisms. (Author)

Descriptors :   (*PLASMA SHEATHS, PROPAGATION), (*RADIOFREQUENCY INTERFERENCE, GAS IONIZATION), RADIO WAVES, SPACE COMMUNICATIONS, ELECTRON DENSITY, MICROWAVES, SHOCK WAVES, RADIOFREQUENCY POWER, XENON, KRYPTON, ARGON, MOLECULES, CONTAMINATION

Subject Categories : Plasma Physics and Magnetohydrodynamics
      Non-radio Communications

Distribution Statement : APPROVED FOR PUBLIC RELEASE