Tunable diode laser spectroscopy and the Beer-Lambert relation has been used to measure the absorption of water vapor both in an absorption cell and in a shock tube. The purpose of this thesis is to develop a laser diagnostic capable of determining species concentration. The correlation between species concentration and absorption is known, and if one is known the other can be calculated. A diode laser was obtained which has a tunable range of 1325.7 - 1400.8 nm and is centered at 1384 nm. An experimental setup was created in which the laser was used to obtain absorption spectroscopy data for water vapor within two separate scenarios- in an absorption cell and in a shock tube. A model was constructed which enabled the calculation of the Voigt profile which in turn was used to determine the absorption coefficient and ultimately enable the utilization of absorption spectroscopy principles to determine species concentration and/or absorption percentage. The experiments for the absorption cell were performed at room temperature. Twenty runs were performed and the average error for all runs was less than one percent. Three runs were performed for the shock-tube experiments. The absorption was calculated at three times- prior to the arrival of the shock, after the incident shock passed, and after the reflected shock passed. The temperatures for these conditions were 296K, 1060K, and 2000K respectively. These experiments showed reasonable agreement with theoretical calculations.

No description available.

Thesis (M.S.)--University of Wisconsin--Madison, 1984. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 87-91).

Thesis (Ph. D.)--Ohio State University, 2004. / Title from first page of PDF file. Document formatted into pages; contains xviii, 154 p.; also includes graphics (some col.). Includes abstract and vita. Advisor: Jeffery C. Rogers, Dept. of Atmospheric Science. Includes bibliographical references (p. 142-153).

Thesis (Ph.D.)--Syracuse University, 2007. / "Publication number: AAT 3295538."

No description available.

This study addressed the problem of water vapor production and distribution in comet P/Halley, based upon interpretation of observational data obtained during the recent 1985-86 apparition. The data was acquired using the Lunar and Planetary Laboratory charge-coupled device (CCD) on the 154-cm Catalina telescope of the University of Arizona Observatories. Our data acquisition system was employed in two modes. The long-slit (∼200") spectroscopy mode covered the wavelength range 5200-10400 Å at a spectral resolution ∼14 Å. The narrow band filter imaging mode allowed two-dimensional mapping of selected cometary emission features, as well as the continuum, with a field of view of roughly 10 arc-min. Both neutral and ionized (H₂O⁺) water species were studied, with emphasis on the ion distribution. This involved comparing long-slit spatial profiles obtained ∼UT 1986 March 05.5, as well as cuts across filter images (∼ March 06.5) centered on the H₂O⁺ 0,8,0-band emission, with the Vega-1 spacecraft in situ ion density measurements (∼ March 06.3). Our March 05 spectroscopic data revealed a central dip, of order 30% relative to the profile peak, in H₂O⁺ column density in the inner coma (inside ∼ 2 x 10⁴ km from the nucleus), which filled in farther tailward. Similarly the BD - 3 plasma detector aboard Vega-1 measured a decrease in local ion density, of roughly 60% at the closest approach distance (∼ 9000 km sunward of the nucleus), relative to the inbound maximum density at R ≃ 12000 km from the nucleus. These results suggest a bimodal flow of ions out of the coma and/or an extended region over which the H₂0 molecules were being ionized. Our imaging data showed that, while the falloff in ion density was relatively rapid sunward of the nucleus, it was much more gradual in the anti-solar direction. This is due to the solar wind sweeping ions from the head of the comet into the plasma tail, whose width was of order 10⁵ km in the inner coma, diverging slowly and breaking up into a ray pattern farther tailward. The distribution of neutral water was mapped out using the [O I] λ6300 emission as diagnostic probe. In contrast to the ions, the H₂0 molecules were mainly confined to the inner few x 10⁴ km of the coma, and exhibited a much more symmetrical distribution. Integration of the [O I] slit profiles, assuming azimuthal symmetry, allowed calculation of the H₂0 production rate, which ranged from ∼ 10²⁸ molecules s⁻¹, when Halley was at a distance r≳ 2 AU from the sun, to a value of ∼ 1.5 x 10³⁰ molecules s⁻¹ for 1986 March 05 (r ≃ 0.78 AU). Using the latter production rate, and assuming a 100/1 production ratio of H₂0/ H₂O⁺, a spatially-averaged, tailward flow speed of ions out of the inner coma, < v⁺ > ≃ 16 km s⁻¹, was derived by integrating our March 05 H₂O⁺ profile, for which the slit was oriented across the coma, just tailward of the nucleus.

A computationally efficient and accurate model is derived for the calculation of the atmospheric transmittance along inhomogeneous paths and within spectral bands dominated by molecular line absorption. It is a Stieltjes integration of transmission weighted by the frequency of occurrence of absorption coefficient within the band. Path inhomogeneitites are accounted for by assuming that the rank of absorption coefficient at any wavenumber is independent of temperature and pressure. The technique is then applied to the ground based radiometric determination of precipitable water. It is found that the technique predicts the behavior of the ρστ water vapor absorption band very well. An RMS disagreement of 11% is found when the model predictions are compared to radiosonde determinations of precipitable water. The model is also applied to the determination of vertical water vapor distributions in the stratosphere given measured effective optical depths as a function of tangent height from a limb scanning satellite. A new iterative reduction technique is introduced which incorporates the transmission model and it is shown to be both numerically stable and rapidly convergent. A comparison of the results with an independent reduction technique shows good overall agreement with a small systematic difference above 20 km. The uncertainty in the measurements, which yields solution uncertainties on the order of 30%, renders this systematic difference unimportant.

Thesis (Ph.D.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / The purpose of the dissertation is to present and discuss the areal distribution of dew point and vapor pressure near the ground in the United States less Hawaii and Alaska. The analysis is based on hourly psychrometric observations at nearly 200 stations for lengths of record which average ten years. Maps of average monthly dew point and its standard deviation, average monthly vapor pressure, and maps presenting four characteristic types of diurnal variation of dew point each month are included in an Appendix to the dissertation. The history of the development of knowledge of water vapor in the atmosphere is also covered in an Appendix to add perspective to the study. The maps are a contribution to the climatography of the United States since the standard maps of average monthly vapor pressure still in use were prepared in 1917, and there are no previous maps showing the several measures of variability of average water vapor content of the air near the ground included in this study [TRUNCATED] / 2031-01-01

Vita. / Digitized by Kansas Correctional Industries