Investigation of polarization spectroscopy for detecting atomic hydrogen in flames /
Two-color, two-photon, laser-induced polarization spectroscopy (LIPS) of atomic hydrogen has been demonstrated for the first time. The pump beam in the measurements was tuned to the two-photon 243-nm n = 1 --> n = 2 resonance of the hydrogen atom. The probe beam was tuned to the single-photon 4...
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| Format: | Thesis eBook |
| Language: | English |
| Published: |
[Place of publication not identified] :
[publisher not identified] ;
2002.
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| Subjects: | |
| Online Access: | Link to OAKTrust copy |
| Summary: | Two-color, two-photon, laser-induced polarization spectroscopy (LIPS) of atomic hydrogen has been demonstrated for the first time. The pump beam in the measurements was tuned to the two-photon 243-nm n = 1 --> n = 2 resonance of the hydrogen atom. The probe beam was tuned to the single-photon 486-nm n = 2 --> n = 4 resonance of the hydrogen atom by fundamental and frequency-doubled beams from a single 486-nm dye laser were used. The probe beam was linearly polarized entering the flame and then transmitted through a crossed polarizer. The change in the leakage intensity through the crossed polarizer in the presence of the pump beam is detected as the LIPS signal. Measurements were performed in an atmospheric pressure, non-premixed, Hâ‚‚/air flame stabilized on near-adiabatic calibration burner (the Hencken burner). The LIPS signal was found to be nearly proportional to the square of the pump beam intensity over a wide range of flame equivalence ratios. Spectral line shapes of hydrogen 1S-4P transition were recorded at flame equivalence ratios ranging from 0.75 to 2.00. H-atom number density distribution profiles were measured in the Hencken burner. Some horizontal profiles were performed to investigate the effect of the nitrogen shroud flow on the H-atom profiles. Extensive vertical scans along the burner centerline were performed for various flame equivalence ratios. The results of the vertical profile measurements will be compared with numerical simulations of the Hencken burner flame. The dependence of the LIPS signal on the pump beam polarization was also studied experimentally. |
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| Item Description: | "Major subject: Mechanical Engineering". Vita. |
| Physical Description: | ix, 88 leaves : illustrations ; 28 cm. Also available online. Issued also on microfiche from Lange Micrographics. |
| Bibliography: | Includes bibliographical references (leaves 83-87). |