View All Items

Title: Examination of observed hydroxyl column abundance behaviors using a mesospheric model.
Creator: Liu, Yan, Florida Atlantic University, Burnett, Elizabeth B., Burnett, Clyde R.
Abstract/Description: OH vertical column abundances have been measured since 1977. Based on this long-term data base, the terrestrial OH abundance trends, such as the high-sun (secX = 1) enhancement of the zenith angle dependence, seasonal variations, and diurnal behaviors, have been observed. Current atmospheric models do not predict these features. In this thesis, a one dimensional photochemical model of the mesosphere has been constructed in order to examine the possibility that these observed effects might...
Show moreOH vertical column abundances have been measured since 1977. Based on this long-term data base, the terrestrial OH abundance trends, such as the high-sun (secX = 1) enhancement of the zenith angle dependence, seasonal variations, and diurnal behaviors, have been observed. Current atmospheric models do not predict these features. In this thesis, a one dimensional photochemical model of the mesosphere has been constructed in order to examine the possibility that these observed effects might originate in this region of the atmosphere. Transport effects are not considered. The model result demonstrates that the observed OH behaviors are not caused by known photochemical reactions in the mesosphere.
Show less
Date Issued: 1990
PURL: http://purl.flvc.org/fcla/dt/14579
Subject Headings: Atmospheric ozone, Photochemistry
Format: Document (PDF)

Title: Terrestrial Absorption in the Sodium D2 Line.
Creator: Novak, Walter T., Burnett, Clyde R., Florida Atlantic University
Abstract/Description: An experimental investigation of the abundance of upper atmospheric sodium at Boca Raton, Florida, using high resolution absorption spectroscopy, is described. The discussion is based primarily on data taken from January to October, 1968, but W. Lammer's data of September through November, 1967, is used for the seasonal analysis. A description of the data and the method of analysing it are presented, with emphasis on the theory underlying a computer method of analysis. Measurements indicate a...
Show moreAn experimental investigation of the abundance of upper atmospheric sodium at Boca Raton, Florida, using high resolution absorption spectroscopy, is described. The discussion is based primarily on data taken from January to October, 1968, but W. Lammer's data of September through November, 1967, is used for the seasonal analysis. A description of the data and the method of analysing it are presented, with emphasis on the theory underlying a computer method of analysis. Measurements indicate a seasonal variation of about a factor of two, with a sharp drop off in late February, 1968. A maximum average monthly abundance of 5.4 ± 2.0 x 10^9 atoms/cm^2 in a vertical column in October, 1967, and a minimum average of 2.6 ± 0.6 x 10 atoms/cm^2 in March, 1968, was measured. The average for the twelve months beginning November, 1967, was 3.6 x 10^9 atoms/cm^2 . In general, uncertainties of the order of 50% are present in the measured abundance determined by a single recorder trace. This value is generally smaller for those traces which are less noisy, and which show a larger amount of terrestrial sodium absorption. No correlation between the abundance and hurricanes has been established. If any correlation exists, it probably is smaller than the uncertainty of our measurements.
Show less
Date Issued: 1968
PURL: http://purl.flvc.org/fau/fd/FA00000802
Subject Headings: Airglow, Thermosphere, Atmosphere, Upper, Solar radiation
Format: Document (PDF)

Title: Excited State Populations of a Residual Hydrogen Impurity in a Helium Afterglow Plasma.
Creator: Marstad, Norman C., Burnett, Clyde R., Florida Atlantic University
Abstract/Description: Time-resolved absolute intensity measurements have been made on the Balmer series lines of a residual hydrogen impurity in a hollowcathode helium afterglow plasma. From these measurements, the excited state populations were calculated and revealed the existence of population inversions in the excited states of hydrogen. In the hydrogen afterglow the maximum average state population shifted upwards from n = 3 at the beginning of the afterglow to progressively higher states until in the late...
Show moreTime-resolved absolute intensity measurements have been made on the Balmer series lines of a residual hydrogen impurity in a hollowcathode helium afterglow plasma. From these measurements, the excited state populations were calculated and revealed the existence of population inversions in the excited states of hydrogen. In the hydrogen afterglow the maximum average state population shifted upwards from n = 3 at the beginning of the afterglow to progressively higher states until in the late afterglow the maximum population was at n = 6. The effects of the helium metastables, both atomic and molecular, were shown to offer no detectable contribution to the observed inversions. Comparison with a theoretical model for a recombining pulsed hydrogen plasma for which inversions had been predicted are favorable and recomb ~nation processes are assumed responsible for the inversions in the lower discrete levels in the hydrogen impurity.
Show less
Date Issued: 1970
PURL: http://purl.flvc.org/fau/fd/FA00000796
Subject Headings: Hydrogen, Helium
Format: Document (PDF)

Title: A COMPARISON OF SODIUM ABUNDANCES CALCULATED FROM DAYLIGHT ABSORPTION AND TWILIGHT EMISSION IN THE D(2) LINE.
Creator: LASHER, RICHARD WILLIAM, Florida Atlantic University, Burnett, Clyde R., Charles E. Schmidt College of Science, Department of Physics
Abstract/Description: A method is presented, in which the Pepsios is used to measure abundances of atomic sodium present in the upper atmosphere as calculated from the twilight glow. These abundances are compared with daylight absorption abundances, also measured using the Pepsios. Ten measurements taken during March, 1971 show an average twilight abundance of (6.1 +- 1.8) x 10^9 atoms/cm^2. This compares with an average absorption abundance of (3.3 +- 1.1) x 10^9 atoms/cm^2. These limited data and their attendant...
Show moreA method is presented, in which the Pepsios is used to measure abundances of atomic sodium present in the upper atmosphere as calculated from the twilight glow. These abundances are compared with daylight absorption abundances, also measured using the Pepsios. Ten measurements taken during March, 1971 show an average twilight abundance of (6.1 +- 1.8) x 10^9 atoms/cm^2. This compares with an average absorption abundance of (3.3 +- 1.1) x 10^9 atoms/cm^2. These limited data and their attendant uncertainties reveal no significant discrepancy between twilight and daytime sodium abundances.
Show less
Date Issued: 1971
PURL: http://purl.flvc.org/fcla/dt/13449
Subject Headings: Sodium--Spectra, Absorption spectra
Format: Document (PDF)

Title: A PSEUDO-SPECTRAL EFFECT FOR THE ACOUSTIC OSCILLATIONS OF A HELIUM AFTERGLOW.
Creator: KILPATRICK, WALLACE DORMAN, Florida Atlantic University, Burnett, Clyde R., Charles E. Schmidt College of Science, Department of Physics
Abstract/Description: The purpose of this experimental study of the helium afterglow in a hollow cathode discharge is to identify the mechanisms which cause an apparent unequal acoustic modulation of the red and violet wings of observed optical spectrum lines. The unequal red-violet effect is traceable to the fact that curved spectrum lines are formed at the exit slit of a monochromator which is equipped with straight entrance and exit slits. Curved spectrum lines emphasize the red and violet wings differently,...
Show moreThe purpose of this experimental study of the helium afterglow in a hollow cathode discharge is to identify the mechanisms which cause an apparent unequal acoustic modulation of the red and violet wings of observed optical spectrum lines. The unequal red-violet effect is traceable to the fact that curved spectrum lines are formed at the exit slit of a monochromator which is equipped with straight entrance and exit slits. Curved spectrum lines emphasize the red and violet wings differently, depending on the light contributions from different portions of the entrance slit, so that spatial variations in the optical image due to acoustic standing waves show unequal integrated light intensities for the modulation of each wing. Only the central portion of the radial standing wave in the afterglow (Bessel function J (kr) distribution) was explored, and the ratio of the red to violet amplitude calculated as 1 : 1.58 agrees qualitatively with experimental results.
Show less
Date Issued: 1970
PURL: http://purl.flvc.org/fcla/dt/13423
Subject Headings: Helium
Format: Document (PDF)

Title: Terrestrial Absorption in the Sodium D2 Line.
Creator: Lammer, Wayne E., Burnett, Clyde R., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Physics
Abstract/Description: An experimental investigation is described in which a Pepsios high resolution pressure scanning s pectrometer is used to measure the absorption of light due to atomic sodium in the upper atmospher e. Design and construction of the spectrometer will be discussed with attention given to unique features of the instrument which were develo ped in this study. An attempt is made to see if any dependence on the abundance of the sodium can be accounted for by the proximity to the ocean or by the...
Show moreAn experimental investigation is described in which a Pepsios high resolution pressure scanning s pectrometer is used to measure the absorption of light due to atomic sodium in the upper atmospher e. Design and construction of the spectrometer will be discussed with attention given to unique features of the instrument which were develo ped in this study. An attempt is made to see if any dependence on the abundance of the sodium can be accounted for by the proximity to the ocean or by the winds and extreme turbulence developed by tropical storms and hurricanes. It is hoped that this data will compliment the existing data found at other latitudes so that a circulation dependence may be found.
Show less
Date Issued: 1967
PURL: http://purl.flvc.org/fau/fd/FA00000786
Subject Headings: Airglow, Thermosphere, Atmosphere, Upper, Solar radiation
Format: Document (PDF)

Title: METASTABLE EXCITATION OF POPULATION INVERSION IN A HELIUM-HYDROGEN AFTERGLOW PLASMA.
Creator: WOO, KING NIEN., Florida Atlantic University, Burnett, Clyde R., Charles E. Schmidt College of Science, Department of Physics
Abstract/Description: A spectroscopic study of a helium-hydrogen afterglow plasma in a pulsed discharge hollow-cathode has been made to determine the energy transfer process which results in a population inversion in atomic hydrogen. Time-resolved emission measurements were made for the Balmer series in hydrogen and self-absorption measurements with lambda 3889 A (2s 3S - 3p 3P) and lambda 4650 A (2s 3sigma - 3p 3n) of helium were taken to monitor the metastable populations. Observations were made as a function of...
Show moreA spectroscopic study of a helium-hydrogen afterglow plasma in a pulsed discharge hollow-cathode has been made to determine the energy transfer process which results in a population inversion in atomic hydrogen. Time-resolved emission measurements were made for the Balmer series in hydrogen and self-absorption measurements with lambda 3889 A (2s 3S - 3p 3P) and lambda 4650 A (2s 3sigma - 3p 3n) of helium were taken to monitor the metastable populations. Observations were made as a function of impurity concentration and as a function of helium pressure. The energy transfer from the 3S atomic metastables appears highly probable with only a minor contribution from the 3sigma molecular metastables.
Show less
Date Issued: 1975
PURL: http://purl.flvc.org/fcla/dt/13746
Subject Headings: Physics--Experiments, Energy transfer--Experiments
Format: Document (PDF)

Title: SPECTROSCOPIC MEASUREMENTS OF OH ABUNDANCES IN THE TERRESTRIAL ATMOSPHERE.
Creator: LANGSTON, JAMES HUTTON, II., Florida Atlantic University, Burnett, Clyde R., Charles E. Schmidt College of Science, Department of Physics
Abstract/Description: Spectroscopic observations were made of the resonance absorption of sunlight by the atmospheric hydroxyl radical (OH). The abundance of 0 terrestrial OH was measured from the Fritz Peak Observatory (39.92 N, 105.50°W) in Colorado during September of 1978. These measurements were made on the absorption of the P1 (1) line of the A^2sigma^+ - x^2pi(O , O) rotational band of OH at 3081.7 A. The instrument used was the PEPSIOS (Poly Etalon Pressure Scanned Interferometric Optical Spectrometer)...
Show moreSpectroscopic observations were made of the resonance absorption of sunlight by the atmospheric hydroxyl radical (OH). The abundance of 0 terrestrial OH was measured from the Fritz Peak Observatory (39.92 N, 105.50°W) in Colorado during September of 1978. These measurements were made on the absorption of the P1 (1) line of the A^2sigma^+ - x^2pi(O , O) rotational band of OH at 3081.7 A. The instrument used was the PEPSIOS (Poly Etalon Pressure Scanned Interferometric Optical Spectrometer) because of its high luminosity - resolution product . The computer methods ·~sed in the analysis procedure are described . These measurements indicated an average daytime vertical column abundance of (5.40 ± 0.67) x 10^13 OH molecules/cm^2.
Show less
Date Issued: 1979
PURL: http://purl.flvc.org/fcla/dt/13968
Subject Headings: Spectrum analysis, Absorption spectra, Atmospheric chemistry
Format: Document (PDF)

Search In

Sort Results By:

Narrow results by:

Collection

Topical Subject

Genre

Type of Resource

Language

Creator

Format

Owner