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HIGH RESOLUTION MEASUREMENTS OF HYDROXYL INFRARED AIRGLOW STRUCTURE (INTERFEROMETER, ISOCON, ROTATIONAL, TEMPERATURE)

Posted on:1986-03-05Degree:Ph.DType:Dissertation
University:Utah State UniversityCandidate:NEAL, PARRIS CORNELFull Text:PDF
GTID:1478390017460735Subject:Physics
Abstract/Summary:
Disturbances in the normally calm atmospheric airglow layer, which causes bright and dark bands or "stripes" to appear, have been observed. These disturbances are attributed to "gravity waves" propagating through the atmosphere. An instrumental capable of resolving the temporal, spatial, and spectral attributes of OH infrared emissions was designed to gather quantitative data on airglow structure.;The interferometer was operated in conjunction with a low-light level infrared imaging isocon camera system provided by the University of Southampton, England. The camera was co-aligned with the telescope to provide an infrared video "eye" for the interferometer.;A bright OH Meinel airglow structure event was recorded on June 15, 1983 from an observation site located at Sacramento Peak, New Mexico. The structures were measured at elevation angles near the horizon. Apparent wavelengths, periods, and phase velocities, of 24 (+OR-) 1 km, 14 (+OR-) 1 minutes, and 28 (+OR-) 2 meters/seconds respectively, were calculated for the recorded structure. The interferometer data show intensity modulations of 20 - 40% within the structure. Rotational temperatures were also calculated using the interferometer spectral data. A mean rotational temperature of 165(DEGREES)K was calculated and temperature modulations of 5 - 10(DEGREES)K were recorded in phase with the intensity modulations.;An optically-compensated interferometer-spectrometer was chosen as the basic instrument to measure this phenomenon. This high-throughput instrument (0.285 cm('2) sr) is an order of magnitude more sensitive than more conventional spectrometers having a noise equivalent spectral radiance of 16 R/cm('-1) at 1.5 (mu)m. A spectral resolution of 2 cm('-1) was obtained. The high-throughput of the optically-compensated interferometer makes possible temporal resolution as short as 30 seconds. Spatial data were obtained by matching the interferometer's high-throughput to a unique optical system which includes a 50-cm diameter telescope. This relatively large diameter Dall-Kirkham telescope maintains the large throughput of the interferometer but narrows the instrument field of view to less than a degree. The spatial resolution of the system is 14 milliradians.
Keywords/Search Tags:Airglow, Resolution, Interferometer, Infrared, Temperature, Rotational
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