CN and C2 Spectroscopy on the Pulsed Ablation of Graphite in the Visible Spectrum

Abstract

An experimental study was conducted on the nanosecond pulsed laser ablation of graphite using a KrF laser at a fluence of 3.8 J/sq cm in Air, Ar, He, and N2. Optical emissions spectroscopy revealed the C2 Swan sequences and the CN Violet sequences. A spectroscopic model was developed to extract the molecular rotational and vibrational temperatures of each excited species for t=0.5-10 microseconds after laser irradiation. The rovibrational temperatures were found to vary with background gas for the CN Violet; however, only the vibrational temperature varied between He and the other background gases for C2 Swan. The rotational and vibrational temperatures were not in equilibrium for both the C2 Swan and CN Violet.

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Document Details

Document Type
Technical Report
Publication Date
Mar 01, 2020
Accession Number
AD1109191

Entities

People

  • Brandon A. Pierce

Organizations

  • Air Force Institute of Technology

Tags

Communities of Interest

  • Advanced Electronics
  • Biomedical
  • C4I
  • Space

DTIC Thesaurus Topics

  • Air Force
  • Chemistry
  • Department Of Defense
  • Energy Transfer
  • Graphitic Materials
  • Heat Of Sublimation
  • Laser Applications
  • Lasers
  • Materials
  • Materials Laboratories
  • Materials Processing
  • Materials Science
  • Materials Testing
  • Nanosecond Time
  • Specific Heat
  • Spectroscopy
  • United States

Fields of Study

  • Physics

Readers

  • Molecular Photonics/Laser Physics
  • Pulsed Power and Plasma Physics.

Technology Areas

  • Directed Energy
  • Directed Energy - Lasers