Microwave Beam Diagnostic of Laser-Induced Plasmas

<p>This thesis describes the use of micro-impulse radar to detect laser-induced plasmas. The MIR actively interrogates the plasma to produce a reflected microwave signal from the plasma, and the device also detects the acoustic signature of the plasma. The acoustic MIR signal is similar to the signal received by a piezoelectric microphone. We show that the magnitudes of both MIR signals are proportional to the plasma intensity as well as to emission line intensities of elements in the plasma. Thus, the MIR, like the microphone signal, can be used to normalize the emission signal to compensate for variations in laser energy. Element concentration studies show that though the laser power can be compensated using the reflected or acoustic signal, they do not correct as well for variation in emission intensity as the concentration is changed. This result suggests that variations in emission like intensity are not solely due to laser power fluctuations.</p>

Name thesis:degree_name

M.S.

Level thesis:degree_level

Campus Access Thesis

Discipline thesis:degree_discipline

Chemistry and Biochemistry

Year

2010

Author dc:creator

• Copenhaver, Ardis

Contributors dc:contributor

• Stanley M. Angel

• Chemistry
• Physical Sciences and Mathematics
• Laser-Induced Breakdown Spectroscopy
• Laser-Induced Plasma
• Microwave

Statement dc:rights

• © 2010, Ardis Copenhaver

Repository record dc:identifier

https://scholarcommons.sc.edu/etd/162

OAI identifier oai:identifier

oai:scholarcommons.sc.edu:etd-1163