Laser Light Absorption Characteristics of a Laser Produced Hydrogen Plasma.

Abstract

Light from a neodymium doped glass laser was focused in Hydrogen gas at pressures from 20 millitorr to 62 atmospheres in order to produce optical breakdown of the gas. In the cases where breakdown was experienced, absorption of the remainder of the laser pulse by the resulting plasma was studied. It was found that the hydrogen plasma had some very distinct absorption characteristics; in that, absorption was very small at pressures slightly exceeding the threshold for optical breakdown, and very strong at pressures above one atmosphere. There was strong evidence of a frequency shift greater than 35 angstroms of the laser light as a result of its transit through the plasma. Photographs of the forward transmitted laser intensity pulses after breakdown were compared in time with a similar pulse in which no breakdown was experienced. (Author)

Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1972
Accession Number
AD0756524

Entities

People

  • James Allen Carlisle

Organizations

  • Naval Postgraduate School

Tags

DTIC Thesaurus Topics

  • Absorption
  • Atmospheres
  • Frequency
  • Frequency Shift
  • Glass Lasers
  • Hydrogen
  • Intensity
  • Laser Pulses
  • Lasers
  • Neodymium
  • Photographs
  • Photography

Fields of Study

  • Engineering
  • Physics

Readers

  • Combustion Dynamics and Shock Wave Physics.
  • Molecular Photonics/Laser Physics
  • Optical Physics and Photonics.

Technology Areas

  • Directed Energy
  • Directed Energy - Lasers