Accession Number:

AD0712281

Title:

PULSED LANGMUIR PROBE MEASUREMENT OF IONIZATION IN A HIGH-PRESSURE PLASMA,

Descriptive Note:

Corporate Author:

VICTORIA UNIV (BRITISH COLUMBIA) DEPT OF PHYSICS

Personal Author(s):

Report Date:

1970-03-16

Pagination or Media Count:

5.0

Abstract:

Measurements with a negatively pulsed probe in an atmospheric-pressure high-density plasma over wide ranges of ionization density 10 to the 15th power to 10 to the 18th powercubic meters, probe voltage 10-400 volts, and flow velocity 5-40 ms have confirmed previous results obtained by Thomas, working at a single voltage and flow velocity in which the current initially falls off with 1t to the y power dependence where y approximately 0.58 and t time. The results together with those of Thomas show good agreement with a theory based on a physical model involving space-charge controlled expansion of the sheath towards its final position. It is expected that this technique of probe operation will afford a simple and sometimes unique method of measuring ionization density with excellent spatial resolution, under high-pressure conditions where the plasma velocity relative to the probe is not accurately known for atmospheric-pressure dc measurements this factor often becomes significant with flow velocities 0.1-1ms. Author

Subject Categories:

  • Test Facilities, Equipment and Methods
  • Plasma Physics and Magnetohydrodynamics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE