Experimental Measurement of Self-Diffusion in a Strongly Coupled Plasma

Abstract

We present a study of the collisional relaxation of ion velocities in a strongly coupled, ultracold neutral plasma on short time scales compared to the inverse collision rate. The measured average velocity of a tagged population of ions is shown to be equivalent to the ion-velocity autocorrelation function. We thus gain access to fundamental aspects of the single-particle dynamics in strongly coupled plasmas and to the ion self-diffusion constant under conditions where experimental measurements have been lacking. Nonexponential decay towards equilibrium of the average velocity heralds non-Markovian dynamics that are not predicted by traditional descriptions of weakly coupled plasmas. This demonstrates the utility of ultracold neutral plasmas for studying the effects of strong coupling on collisional processes, which is of interest for dense laboratory and astrophysical plasmas.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Aug 04, 2016
Accession Number
AD1010157

Entities

People

  • J. Daligault
  • P. Mcquillen
  • T. C. Killian
  • T. K. Langin
  • T. S. Strickler

Organizations

  • Rice University

Tags

Communities of Interest

  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Brownian Motion
  • Diffusion Coefficient
  • Dynamics
  • Electrons
  • Equations
  • Ionization
  • Kinetic Theory
  • Kinetics
  • Laser Beams
  • Laser Induced Fluorescence
  • Lasers
  • Measurement
  • Molecular Dynamics
  • Optical Pumping
  • Simulations
  • Three Dimensional
  • Two Dimensional

Fields of Study

  • Physics

Readers

  • Molecular Photonics/Laser Physics
  • Plasma Physics / Magnetohydrodynamics
  • Systems Analysis and Design

Technology Areas

  • Space
  • Space - Hall-Effect Thruster