Shockfronts as Model Targets in Laser-Plasma Interaction Experiments,

Abstract

We have used a shockfront, produced in a small, electrothermal shocktube filled with 40-60 torr D2, as a model target for studies of the interaction of intense laser light with hot, dense, inhomogeneous plasmas. The CO2 laser pulse (lambda = 10.6 micrometer; 100-500 psec FWHM; typical energy 100 mJ) is tightly focussed, at an oblique angle, onto the shockfront axis, and a laser-Schlieren shockfront detection system fires the laser at the instant the Mach-5 shockfront passes into focus. The shockfront, whose motion is negligible on the time scale of the laser pulse is ionized by optical breakdown. When the laser pulse and the shockfront are properly synchronized, we observe energetic electrons (40-140 keV) to be emitted in a narrow cone centered on the shocktube axis. Our measurements of the angular distribution and energy spectrum of these electrons are in agreement with the predictions of the theory of resonance absorption of laser light by plasmas.

Document Details

Document Type
Technical Report
Publication Date
Jul 01, 1981
Accession Number
ADP000274

Entities

People

  • Eli Yablonovitch
  • Paul Kolodner

Tags

DTIC Thesaurus Topics

  • Absorption
  • Agreements
  • Carbon Dioxide Lasers
  • Detection
  • Diffraction
  • Electromagnetic Spectra
  • Electrons
  • Laser Pulses
  • Lasers
  • Measurement
  • Micrometers
  • Resonance
  • Resonance Absorption
  • Shock Tubes
  • Spectra
  • Tubes

Fields of Study

  • Physics

Readers

  • Electromagnetic Wave Scattering and Antenna Radiation Engineering
  • Fluid Dynamics.
  • Pulsed Power and Plasma Physics.

Technology Areas

  • Directed Energy
  • Microelectronics