A light Scattering Technique for Studying Brownian Motion

Abstract

The purpose of the work was to study the light scattered from a simple statistical medium that consisted of a monodispersed ensemble of spherical, Brownian particles. The light from a helium-neon laser operating at a wavelength of 632.8 nm was scattered from a dilute water suspension of the particles, which are polystyrene spheres of diameter 0.557 micrometers. The spectrum of the scattered light is a very narrow Lorentzian whose half width at half height is related to the diffusion constant of the particles. An experiment that employs the technique of pulse interval analysis to analyze the scattered light spectrum is described in detail. The results of this experiment yielded a spectral linewidth that is caused not only by the diffusive motion, but also by the convective motion of the particles.

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Document Details

Document Type
Technical Report
Publication Date
Sep 01, 1972
Accession Number
AD0750110

Entities

People

  • Merrill E. Milham

Tags

Communities of Interest

  • Advanced Electronics
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Amplifiers
  • Brownian Motion
  • Detectors
  • Helium Neon Lasers
  • High Voltage
  • Light Scattering
  • Measurement
  • New Jersey
  • New York
  • Operational Amplifiers
  • Photomultiplier Tubes
  • Power Supplies
  • Probability
  • Refractive Index
  • Scattering
  • Spectra
  • Time Intervals

Fields of Study

  • Physics

Readers

  • Aerosol Science/Aerosol Physics
  • Spectroscopy.

Technology Areas

  • Directed Energy