Open Access. Powered by Scholars. Published by Universities.®
Atomic, Molecular and Optical Physics Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Discipline
- Institution
- Keyword
-
- Atmospheric ozone (1)
- Clay soils (1)
- Complementarity (1)
- Depolarization spectra (1)
- Energy transfer (1)
-
- Error analysis (Mathematics) (1)
- Field-effect transistors--Design and construction (1)
- Frequency spectra (1)
- Gallium arsenide (1)
- Gamma ray spectrometer--Design and construction (1)
- Gas lasers (1)
- Hyperfine structure (1)
- Indium alloys (1)
- Indium antimonide crystals (1)
- Infrared detectors (1)
- Infrared spectroscopy (1)
- Laser photochemistry (1)
- Magnesium (1)
- Matrix derivatives (1)
- Molecular beam epitaxy (1)
- Polarization interference spectroscopy (1)
- Polarization spectroscopy (1)
- Pressure broadening (1)
- Quantum theory (1)
- Rare gas (1)
- Rubidium--Isotopes--Spectra (1)
- Semiconductor lasers--Materials--Optical properties (1)
- Soil remediation (1)
- Target acquisition (1)
- Trichloroethylene (1)
Articles 1 - 14 of 14
Full-Text Articles in Atomic, Molecular and Optical Physics
Study Of The Long-Term Desorption Of Trichloroethylene From Clay Soils Using Infrared Spectroscopy, Mary P. Stager
Study Of The Long-Term Desorption Of Trichloroethylene From Clay Soils Using Infrared Spectroscopy, Mary P. Stager
Theses and Dissertations
Slow desorption of contaminants from soil presents one of the greatest challenges to modeling contaminant fate and transport and implementing effective remediation technologies. The kinetics of long-term desorption of trichloroethylene (TCE) from powdered clay soils were studied to determine the desorption rates and mechanism. Infrared absorption spectroscopy was used to monitor the concentration of TCE desorbed from contaminated flint clay for 71 hours. Observed gas phase TCE concentrations as a function of time were compared to that predicted by a one-site Langmuir desorption mechanism. The Langmuir model, with a single type of bonding site, did not account for the release …
A Comparison Of Methods For Estimating Rms Error: A `Brute Force" Approach Versus A Mathematically-Elegant Approach, As Applied To The Calculation Of A Specific Retrieval Error For A Limb-Scanning Microwave Radiometer-Spectrometer, Larry L. Johnson
Theses and Dissertations
The Millimeter-wave Atmospheric Sounder (MAS) is a high resolution limb- scanning microwave radiometer-spectrometer which has been flown aboard the Space Shuttle. The instrument was designed to sense the microwave emission from several upper atmospheric constituents, including water vapor and ozone. The resonant frequencies of water vapor and ozone are extremely close (183 and 184 GHz, respectively), so that the high-frequency wing of the water vapor spectrum overlaps the low frequency wing of the ozone spectrum. Consequently, the measured ozone spectrum incorporates a slight water vapor contribution; therefore, the retrieved ozone profile is dependent on the true water vapor profile. The …
A Portable Compton Gamma-Ray Camera Design, Brian L. Evans
A Portable Compton Gamma-Ray Camera Design, Brian L. Evans
Theses and Dissertations
The purpose of this research is to investigate the angular resolution, efficiency, and energy resolution possible from a portable Compton camera gamma ray imaging system for possible use in the field of nuclear nonproliferation. The proposed device uses room temperature semiconductor and position sensitive scintillation detectors. The position and energy resolution (and their energy dependence) of a room temperature lithium drifted silicon (Si(Li)) detector and a position sensitive thallium -doped sodium iodide (NaI(Tl)) scintillation detector are investigated. The position and energy resolution of the position sensitive scintillation detector is also modeled computationally, and the results compared to measured data. An …
Steady-State Kinetics Of Br(2P1/2) Yields Co2(101) Electronic-To-Vibrational Energy Transfer Laser System, Stephen J. Karis
Steady-State Kinetics Of Br(2P1/2) Yields Co2(101) Electronic-To-Vibrational Energy Transfer Laser System, Stephen J. Karis
Theses and Dissertations
Steady state photolysis experiments were conducted to gain information relevant to the construction of a continuous wave electronic to vibrational pumped infrared laser. An Ar+ laser =488 µm) was used to produce the electronically excited state Br(2P1/2) (Br*) via photolysis of molecular bromine. Energy was then transferred to the near resonant vibrational state CO2(101) (CO2) via the collisional quenching of Br* by CO2. The dependence of the 2.71 µm Br* and 4.3 µm CO2 emissions on CO2 pressure was measured, as well as …
Optical Characterization Of Indium Arsenide Antimonide Semiconductors Grown By Molecular Beam Epitaxy, Michael A. Marciniak
Optical Characterization Of Indium Arsenide Antimonide Semiconductors Grown By Molecular Beam Epitaxy, Michael A. Marciniak
Theses and Dissertations
The material parameters and crystalline quality of undoped, MBE-grown InAs1-xSbx nearly lattice-matched to (100) GaSb (-0.617% ≤ Δ a-a ≤ +0.708%) similar to material used for mid-infrared semiconductor lasers were determined by optical characterization. Absorption measurements at temperatures between 6-295 K determined the energy gap and wavelength-dependent absorption coefficient for each sample. The compositional dependence of the energy gap was anomalous when compared to previously reported data, suggesting phase separation existed in the material. The samples were also studied by temperature- and excitation-dependent photoluminescence (PL), which, for the majority of cases, showed only a single band-edge peak, …
Collisional Dynamics Of The Rubidium 52P Levels, Matthew D. Rotondaro
Collisional Dynamics Of The Rubidium 52P Levels, Matthew D. Rotondaro
Theses and Dissertations
The collisional dynamics of the 52P levels in rubidium has been examined using steady-state laser absorption and spectrally-resolved laser induced fluorescence techniques. State-to-state cross-sections for energy transfer between Zeeman split levels ranged from 16-248 °A2 for collisions with nitrogen and rare gases. These energy transfer cross-sections exhibit a significant dependence on (J,mj) state and certain symmetry relationships are demonstrated. A sub-Doppler spectrum of the Zeeman split levels indicating the isotopic shift in the D1 line of 106 ± 35 was obtained using laser saturation spectroscopy.
Non-Imaging Infrared Spectral Target Detection, Matthew R. Whiteley
Non-Imaging Infrared Spectral Target Detection, Matthew R. Whiteley
Theses and Dissertations
Automatic detection of time-critical mobile targets using spectral-only infrared radiance data is explored. A quantification of the probability of detection, false alarm rate, and total error rate associated with this detection process is provided. A set of classification features is developed for the spectral data, and these features are utilized in a Bayesian classifier singly and in combination to provide target detection. The results of this processing are presented and sensitivity of the class separability to target set, target configuration, diurnal variations, mean contrast, and ambient temperature estimation errors is explored. This work introduces the concept of atmospheric normalization of …
Ohmic Contact To Ion Implanted Gallium Arsenide Antimonide For Application To Indium Aluminum Arsenide-Gallium Arsenide Antimonide Heterostructure Insulated-Gate Field Effect Transistors, Kenneth G. Merkel Ii
Ohmic Contact To Ion Implanted Gallium Arsenide Antimonide For Application To Indium Aluminum Arsenide-Gallium Arsenide Antimonide Heterostructure Insulated-Gate Field Effect Transistors, Kenneth G. Merkel Ii
Theses and Dissertations
The p-channel In0.52Al0.48As-GaAs1-xSbx heterostructure insulated-gate field effect transistor (p-HIGFET) is a candidate for complementary integrated circuits due to superior cutoff characteristics and low gate leakage current. Advancement of the In0.52Al0.48As-GaAs1-xSbx p-HIGFET requires improved source-drain design. Five main tasks were accomplished to achieve this goal. First, thermal limits of the In0.52Al0.48As-GaAs0.51Sb0.49 HIGFET were investigated. Second, the temperature dependence of band gap and impurity energies were determined for beryllium doped In0.52Al0.48. Third, high acceptor concentrations were obtained …
Bandwidth And Additive Bandwidth Of Graphs, Maria Kujawski
Bandwidth And Additive Bandwidth Of Graphs, Maria Kujawski
Honors Capstone Projects and Theses
No abstract provided.
Measurement Of Hyperfine Coupling Constants Of The 5d²D₃/₂ And 5d²D₅/₂ Levels In Atomic Cesium Using Polarization Quantum Beat Spectroscopy, Wo Yei
Physics Theses & Dissertations
Accurate measurements of hyperfine constants have revealed effects that can not be explained by a simple hydrogenic picture of the alkali atoms such as cesium [1-3]. More precise experimental results and theoretical treatments are in demand for the alkali elements, especially for atomic cesium because of its wide range of applications. Therefore, it is essential to understand its atomic and nuclear structure. Precision measurement of its excited-states properties such as hyperfine structure provides global information on nuclear charge and current distributions and also serves as a check to the theory and a calibration of calculated excited state wave functions. Accurate …
Excited-State Magnesium-Rare Gas Optical Collisions, Rosemary A. Lasell
Excited-State Magnesium-Rare Gas Optical Collisions, Rosemary A. Lasell
Physics Theses & Dissertations
Polarization and intensity spectra have been obtained for excited-state magnesium (3s3p 1P1) - rare gas optical collisions. The magnesium was excited by a linearly polarized laser tuned to the 3s21s0 → 3s3p 1P1 atomic transition at 285 nm. A second linearly polarized laser was tuned near the 3s3p 1P1 → 3s5s 1S0 transition at 571 nm (experiment A) and near the 3s3p 1P1 → 3s4d 1D2 transition at 553 nm (experiment B). The polarization vector of the second laser was oriented either parallel or …
Theoretical Investigation Of Two-Color, Two-Photon, 6s(2)S(1/2) → 5d(2)D(J) → 11p(2)P(3/2) Excitation And Depolarization Spectra In Atomic Cesium, Boris Dobrydnev
Theoretical Investigation Of Two-Color, Two-Photon, 6s(2)S(1/2) → 5d(2)D(J) → 11p(2)P(3/2) Excitation And Depolarization Spectra In Atomic Cesium, Boris Dobrydnev
Physics Theses & Dissertations
The theoretical investigation of two-photon, two-color intensity and depolarization spectra for the 6s2S1/2 → 5d2Dj → 11p2P3/2 transition in atomic caesium is considered. For quadrupole-dipole transitions the dependence of excitation from the ratio of reduced matrix elements is shown. The experimental method of determination of the value and sign of the ratio is proposed. Comparison of results for co- and counterpropagating beams revealed the strong dependence of the transition rate on the relative beam directions. Analysis of the influence of the external electric field on the process of absorption is presented. …
Precision Measurement Of Relative Dipole Matrix Elements In Atomic Sodium, Rodney P. Meyer
Precision Measurement Of Relative Dipole Matrix Elements In Atomic Sodium, Rodney P. Meyer
Physics Theses & Dissertations
Relative dipole matrix elements are measured by means of a new spectroscopic technique called polarization interference spectroscopy. It is a two-color two-photon nonresonant process that maps the matrix elements into the energy domain by means of quantum mechanical interference. The technique measures the relative magnitude of the reduced matrix elements, particularly those involving excited states, to accuracies that are an order of magnitude better than previously available. Also, for the first time the relative phase of the reduced matrix elements is measured. The ratio of reduced matrix elements for the transitions 3s 2S1/2 →3P 2P3/2 →5s …
Search For Metastability Of 2s Muonic Neon, Bernard Wilhelm Bach
Search For Metastability Of 2s Muonic Neon, Bernard Wilhelm Bach
Dissertations, Theses, and Masters Projects
An experiment was performed at the Paul Scherrer Institut (PSI) to establish the conditions for the metastability of the 2S-state of muonic neon. The muonic atoms were formed by stopping negative muons in the neon-filled target chamber of the PSI cyclotron trap. A pair of intrinsic germanium detectors were used in coincidence to search for the two photon decay of the 2S-state. Both energy and time information from two photon events were written to disk for off-line analysis. Data were accumulated for neon pressures of 40 and 400 Torr. The data were then searched for evidence of two photon transitions …