Accession Number:

ADA242941

Title:

Picosecond Laser Breakdown Thresholds in Gases

Descriptive Note:

Final scientific rept. 28 Feb 90-30 Sep 91,

Corporate Author:

TENNESSEE UNIV SPACE INST TULLAHOMA CENTER FOR LASER APPLICATIONS

Personal Author(s):

Report Date:

1991-09-30

Pagination or Media Count:

65.0

Abstract:

An experimental investigation of laser sustained plasmas LSP was begun in 1984 at The University of Tennessee Space Institute UTSI. The objective of this research was to understand the basic physical mechanisms of the LSP and determine their influence on stability, laser power absorption, thermal radiation loss and thermal conversion efficiency. The approach used was to create the LSP in argon using a continuous wave CW carbon dioxide laser at moderate powers 1.5 kW and to obtain detailed measurements of the plasma temperature field by using a modern digital image processing computer to acquire spectral images of the plasma emission. Using the measured temperature field, the laser power absorption and thermal plasma emission could be calculated at any point within the LSP to provide a detailed understanding of the energy conversion processes. These results indicate that there are no fatal flaws in the concept utilizing the LSP for laser thermal propulsion, and suggest that the internal energy conversion processes can be sufficiently well controlled through the optical and flow configurations to provide an efficient, high specific impulse propulsion system.

Subject Categories:

  • Optics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE