| dc.identifier.uri | http://hdl.handle.net/11401/77105 | |
| dc.description.sponsorship | This work is sponsored by the Stony Brook University Graduate School in compliance with the requirements for completion of degree. | en_US |
| dc.format | Monograph | |
| dc.format.medium | Electronic Resource | en_US |
| dc.language.iso | en_US | |
| dc.publisher | The Graduate School, Stony Brook University: Stony Brook, NY. | |
| dc.type | Dissertation | |
| dcterms.abstract | Spectroscopic methods for retrieval of atmospheric data such as pressure, temperature, and concentration depend on the accurate characterization of spectral line shapes. As a model system, the P(11) line of the υ <sub>1</sub>+υ <sub>3</sub> band of acetylene, near 1.5 µm, was explored in great detail using a high resolution spectrometer based on a frequency comb-referenced continuous wave laser. This spectrometer is capable of measurements with frequency accuracy better than 1 part in 10<super>11</super>. This allows for unprecedented accuracy in experimental data exploring the effects contributing to a spectral line shape. Direct absorption measurements on acetylene in a cell capable of modeling atmospheric conditions of varying temperatures and pressures have been made. Line shapes due to acetylene-acetylene and acetylene-nitrogen collisions were investigated at pressures up to 1 atm. and temperatures between 125 K and 296 K. Fitting line shapes in a practical way requires models that have parameters that scale realistically with temperature and pressure. Several of the most common line shape models were examined including models with broadening, shift, narrowing, and speed-dependent effects. Fits resulted in line shape parameters with large improvements in accuracy over previous measurements due to the frequency accuracy of the spectrometer. | |
| dcterms.abstract | Spectroscopic methods for retrieval of atmospheric data such as pressure, temperature, and concentration depend on the accurate characterization of spectral line shapes. As a model system, the P(11) line of the υ <sub>1</sub>+υ <sub>3</sub> band of acetylene, near 1.5 µm, was explored in great detail using a high resolution spectrometer based on a frequency comb-referenced continuous wave laser. This spectrometer is capable of measurements with frequency accuracy better than 1 part in 10<super>11</super>. This allows for unprecedented accuracy in experimental data exploring the effects contributing to a spectral line shape. Direct absorption measurements on acetylene in a cell capable of modeling atmospheric conditions of varying temperatures and pressures have been made. Line shapes due to acetylene-acetylene and acetylene-nitrogen collisions were investigated at pressures up to 1 atm. and temperatures between 125 K and 296 K. Fitting line shapes in a practical way requires models that have parameters that scale realistically with temperature and pressure. Several of the most common line shape models were examined including models with broadening, shift, narrowing, and speed-dependent effects. Fits resulted in line shape parameters with large improvements in accuracy over previous measurements due to the frequency accuracy of the spectrometer. | |
| dcterms.available | 2017-09-20T16:51:58Z | |
| dcterms.contributor | Sears, Trevor J | en_US |
| dcterms.contributor | Hanson, David | en_US |
| dcterms.contributor | Johnson, Philip | en_US |
| dcterms.contributor | Gamache, Robert. | en_US |
| dcterms.creator | Cich, Matthew James | |
| dcterms.dateAccepted | 2017-09-20T16:51:58Z | |
| dcterms.dateSubmitted | 2017-09-20T16:51:58Z | |
| dcterms.description | Department of Chemistry. | en_US |
| dcterms.extent | 102 pg. | en_US |
| dcterms.format | Monograph | |
| dcterms.format | Application/PDF | en_US |
| dcterms.identifier | http://hdl.handle.net/11401/77105 | |
| dcterms.issued | 2014-12-01 | |
| dcterms.language | en_US | |
| dcterms.provenance | Made available in DSpace on 2017-09-20T16:51:58Z (GMT). No. of bitstreams: 1
Cich_grad.sunysb_0771E_11939.pdf: 3306843 bytes, checksum: dab58301426511044ba5216c7a3a9123 (MD5)
Previous issue date: 1 | en |
| dcterms.publisher | The Graduate School, Stony Brook University: Stony Brook, NY. | |
| dcterms.subject | acetylene, frequency comb, line shape, saturated absorption, speed dependence, temperature dependence | |
| dcterms.subject | Physical chemistry | |
| dcterms.title | High Resolution, Frequency Comb-Referenced Measurements of Spectral Line Shapes | |
| dcterms.type | Dissertation | |
