ON THE EXPERIMENTAL DETERMINATION OF MICROSTATE DISTRIBUTIONS ASSOCIATED WITH GAS-SURFACE SCATTERING,

Abstract

A method for determining velocity distributions in surface-scattered molecular beams is described. Time-of-flight effects in the modulated beams provide the means for extracting the velocity distributions from measured waveforms in the number density. A generalization of the method, applicable to the investigation of velocity-residence time distributions, is proposed for interactions in which the surface residence times are of the order of the molecular flight times. A system of 'broad-band' lock-in beam detection, useful for signal-to-noise enhancement, is also described. For demonstrative purposes, the method is used to examine collisional effects in direct beams generated with an array of capillary tubes. Evidence is found that the observed collisional reductions in beam intensity are associated with both internal scattering inside the capillary tubes and self-collision in the highly directional post-array density field. (Author)

Document Details

Document Type
Technical Report
Publication Date
Oct 01, 1966
Accession Number
AD0646320

Entities

People

  • J. D. Mcclure

Organizations

  • Boeing

Tags

DTIC Thesaurus Topics

  • Capillary Tubes
  • Collisions
  • Detection
  • Directional
  • Intensity
  • Microvessels
  • Molecular Beams
  • Scattering
  • Tubes
  • Waveforms

Fields of Study

  • Physics

Readers

  • Acoustical Oceanography.
  • Molecular Photonics/Laser Physics
  • Plasma Physics.