You are here

PLASMA TEMPERATURE MEASUREMENTS IN THE CONTEXT OF SPECTRAL INTERFERENCE

Download pdf | Full Screen View

Date Issued:
2016
Abstract/Description:
The path explored in this thesis is testing a plasma temperature measurement approach that accounts for interference in a spectrum. The Atomic Emission Spectroscopy (AES) technique used is called Laser Induced Breakdown Spectroscopy (LIBS) and involves focusing a laser pulse to a high irradiance onto a sample to induced a plasma. Spectrally analyzing the plasma light provides a "finger print" or spectrum of the sample. Unfortunately, spectral line broadening is a type of interference encountered in a LIBS spectrum because it blends possible ionic or atomic transitions that occur in plasma. To make use of the information or transitions not resolved in a LIBS spectrum, a plasma temperature method is developed. The basic theory of a LIBS plasma, broadening mechanisms, thermal equilibrium and distribution laws, and plasma temperature methods are discussed as background support for the plasma temperature method tested in this thesis. In summary, the plasma temperature method analyzes the Full Width at Half the Maximum (FWHM) of each spectral line for transitions provided from a database and uses them for temperature measurements. The first implementation of the temperature method was for simulated spectra and the results are compared to other conventional temperature measurement techniques. The temporal evolution of experimental spectra are also taken as a function of time to observe if the newly developed temperature technique can perform temporal measurements. Lastly, the temperature method is tested for a simulated, single element spectrum when considering interferences from all the elements provided in an atomic database. From stimulated and experimental spectra analysis to a global database consideration, the advantages and disadvantages of the temperature method are discussed.
Title: PLASMA TEMPERATURE MEASUREMENTS IN THE CONTEXT OF SPECTRAL INTERFERENCE.
20 views
11 downloads
Name(s): Seesahai, Brandon, Author
Baudelet, Matthieu, Committee Chair
University of Central Florida, Degree Grantor
Type of Resource: text
Date Issued: 2016
Publisher: University of Central Florida
Language(s): English
Abstract/Description: The path explored in this thesis is testing a plasma temperature measurement approach that accounts for interference in a spectrum. The Atomic Emission Spectroscopy (AES) technique used is called Laser Induced Breakdown Spectroscopy (LIBS) and involves focusing a laser pulse to a high irradiance onto a sample to induced a plasma. Spectrally analyzing the plasma light provides a "finger print" or spectrum of the sample. Unfortunately, spectral line broadening is a type of interference encountered in a LIBS spectrum because it blends possible ionic or atomic transitions that occur in plasma. To make use of the information or transitions not resolved in a LIBS spectrum, a plasma temperature method is developed. The basic theory of a LIBS plasma, broadening mechanisms, thermal equilibrium and distribution laws, and plasma temperature methods are discussed as background support for the plasma temperature method tested in this thesis. In summary, the plasma temperature method analyzes the Full Width at Half the Maximum (FWHM) of each spectral line for transitions provided from a database and uses them for temperature measurements. The first implementation of the temperature method was for simulated spectra and the results are compared to other conventional temperature measurement techniques. The temporal evolution of experimental spectra are also taken as a function of time to observe if the newly developed temperature technique can perform temporal measurements. Lastly, the temperature method is tested for a simulated, single element spectrum when considering interferences from all the elements provided in an atomic database. From stimulated and experimental spectra analysis to a global database consideration, the advantages and disadvantages of the temperature method are discussed.
Identifier: CFH2000140 (IID), ucf:46057 (fedora)
Note(s): 2016-12-01
B.S.P.S.E.
College of Optics and Photonics, CREOL
Bachelors
This record was generated from author submitted information.
Subject(s): Laser-Induced Plasma
Local Thermodynamic Equilibrium
Plasma Temperature
Plasma Broadening
Spectral Interference
Boltzmann Plot
Persistent Link to This Record: http://purl.flvc.org/ucf/fd/CFH2000140
Restrictions on Access: campus 2017-12-01
Host Institution: UCF

In Collections