| The Time Dependent Spectral Emission of Proton Bombarded Aerogels |
04 AUG 1998 |
82 pages |
| Authors:
E. W. Marsh; ARIZONA UNIV TUCSON DEPT OF PHYSICS
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 | The University of Arizona 2 MV Van de Graaff accelerated 1 MeV protons to bombard aerogel targets. The spectroscopic emission characteristics of proton bombarded aerogels 1.68 mm - 5.50 mm thick were studied, particularly the emission as a function of bombardment time. It was discovered that the intensities of proton bombarded aerogel emissions depend on proton beam current, emitted wavelength, aerogel thickness, observation position inside of ... |
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| Scanning Tunneling Microscopy of III-V Semiconductors |
06 JUN 94 |
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| Authors:
John D. Dow; ARIZONA UNIV TUCSON DEPT OF PHYSICS
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 | Scanning tunneling microscopy and theory were combined to create novel depressive quantum dots at room temperature on the (110) surfaces of InSb --- dots which merit further exploration as potential nanopixels for tiny-device lithography; develop a strained-layer superlattice model of high-temperature superconductivity; image, understand, and make models of single-atom-high steps on III-V surfaces; invent and exploit a new kind of spectroscopy of surface states of semiconductors, called tipology; develop phenomenological ... |
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| Polarized Light Scattering from Perfect and Perturbed Surfaces and Fundamental Scattering Systems |
29 FEB 92 |
62 pages |
| Authors:
William S. Bickel; ARIZONA UNIV TUCSON DEPT OF PHYSICS
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| CONTENTS: Light scattering from a sphere on or near a surface; Light scattering from a sphere on or near a surface: Errata; Coherent fluorescent emission and scattering from a uniform cylinder; Coherent fluorescent emission and scattering from a uniform sphere; Light scattering mueller matrix from a fiber as a function of MgO contamination; Experimental light-scattering mueller matrix for a fiber on a reflecting optical surface as a function of incident ... |
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| Application of Solar Seismology to Study of the Convection Zone |
09 MAY 90 |
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| Authors:
Henry A. Hill; ARIZONA UNIV TUCSON DEPT OF PHYSICS
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| Progress has been made in the program to use solar seismology as a tool for the understanding and potentially the forecasting of solar variability. Changes in the velocity of sound profile and nonadiabatic effects in the internal equilibrium condition of the convection zone over a six year period have been inferred from observed changes in the frequencies of low-order acoustic moses and intermediate degree f-modes. These changes may be associated ... |
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| Application of Solar Seismology to Study of the Convection Zone |
22 APR 87 |
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| Authors:
Henry A. Hill; ARIZONA UNIV TUCSON DEPT OF PHYSICS
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| In the 1970's an observational technique for the study of solar oscillations with periods longer than 5 min was developed at SCLERS. The technique yields information about the temperature eigenfunction of an oscillation at the extreme solar limb. The primary goal of the observational program for 1982-1986 was to use this technique to systematically increase the data base for the study of solar oscillations. Because of the complexity of the ... |
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| Time-of-Flight Spectroscopy of Ionic and Metastable Fragments from Dissociating Molecules |
14 OCT 85 |
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| Authors:
Willis E. Lamb Jr.; L. C. McIntyre Jr; ARIZONA UNIV TUCSON DEPT OF PHYSICS
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| This research involved the dissociation of hydrogen-containing molecules by electron impact and the subsequent measurement of the velocity of proton or metastable hydrogen fragments using time-of-flight methods. The proton velocity distribution resulting from dissociation of the hydrogen halides resulted in information on excited states of the corresponding molecular ions with inner-shell electron holes. Another completed project involved the proton velocity distribution from electron bombardment of the triatomic molecules, water and ... |
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| Development of an Interferometric Technique for Reduction of Background Radiation at 10 Micrometers |
1984 |
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| Authors:
ARIZONA UNIV TUCSON DEPT OF PHYSICS
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| This report concerns the final status of the ONR contract entitled Development of an Interferometric Technique for Background Radiation at 10 micrometers. The purpose of the proposed instrument was to improve the detectability of a background limited source in the atmospheric window from 8 to 12 micrometers. Such an improvement would be possible if the photons arising from the source and background could be discriminated interferometrically such that the desired ... |
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| Information Content and Sensitivity of Matrix Elements to Structural Changes in Complex Scattering System |
JUN 1983 |
44 pages |
| Authors:
W. S. Bickel; ARIZONA UNIV TUCSON DEPT OF PHYSICS
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| Physics Department researchers at the University of Arizona investigated a number of basic problems that are central to understanding light scattered from complex systems. They started with simple geometrical systems-- spherical and cylindrical geometries with known optical constants that are directly amenable to theory. Theorists can calculate exactly every scattering property (the matrix elements) of these systems and experimentalists can measure them with arbitrarily high accuracy and precision. Yet some ... |
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| Study of Solar Oscillations |
05 JUN 81 |
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| Authors:
Henry A. Hill; ARIZONA UNIV TUCSON DEPT OF PHYSICS
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| Recent observational evidence on solar oscillations is reviewed; this evidence strongly favors the global interpretation for much of the observed spectrum. Implications of these observations for the study of the solar interior and atmosphere are discussed. An observational program and supporting theoretical program are described in which the oscillations are detected via solar diameter measurements at Santa Catalina Lab. for Experimental Relativity by Astrometry. The main goal of these programs ... |
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| Time-offlight Spectroscopy of Molecular Structure, Collision Processes, and Gas-Surface Interactions. |
29 JUL 1980 |
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| Authors:
Willis E. Lamb Jr.; Laurence C. McIntyre Jr; ARIZONA UNIV TUCSON DEPT OF PHYSICS
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| Progress in molecular physics research using time-of-flight techniques to measure velocity distributions of fragments from dissociating molecules is reported. Electron bombardment at energies between 20 and 100 eV was used to dissociate the molecules, and only fragments with kinetic energies greater than about 1 eV were detected. Both metastable hydrogen atoms and one-, two-, and three-atom hydrogenic charged fragments were detected. Special selective detectors were designed and built for metastable ... |
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| Determination of Optical Constants for Powdered Materials in the 10 Micron Infrared Region. |
03 SEP 1979 |
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| Authors:
Donald R. Huffman; ARIZONA UNIV TUCSON DEPT OF PHYSICS
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| In order to successfully tailor the aerosol to the specific need we should be able to engineer the optical properties of the particulates, that is to calculate the performance of various systems and to produce the one that most closely fits the desired characteristics. In order to accomplish this optical engineering of aerosols the following two things are necessary: (1) A catalogue of the wavelength-dependent optical constants for various solids ... |
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| Studies of Extinction by Small Particles in the 10 Micron Spectral Region |
JUL 1978 |
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| Authors:
Donald R. Huffman; ARIZONA UNIV TUCSON DEPT OF PHYSICS
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| With the increasing importance of lasers in our technological world and the continually increasing power levels becoming available, it is inevitable that laser weapons will play an important role in various phases of modern warfare. As dependence on lasers increases, there is a need to know how these intense light beams are affected by airborne particles, either intentionally or accidentally produced, whether man-made or natural. Obvious defensive mechanisms against laser ... |
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| Introduction to and Review of Beam-Foil Spectroscopy, |
JAN 1977 |
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| Authors:
Stanley Bashkin; ARIZONA UNIV TUCSON DEPT OF PHYSICS
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| This paper divides the subject into four separate parts. In the first, some of the historical developments of beam-foil spectroscopy are reviewed and examples from various stages in the increasing sophistication of the experiments are given. The second part concentrates on the determination of spectra from different stages of ionization of various elements. The third is concerned with the determination of the lifetimes of excited electronic states. The last part ... |
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| Future Directions for Beam-Foil Spectroscopy, |
JAN 1976 |
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| Authors:
S. Bashkin; ARIZONA UNIV TUCSON DEPT OF PHYSICS
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| The beam-foil source has proved to be so useful for the study of atomic energy levels that it is almost trivial to propose a variety of new experiments involving new elements, higher energies, a broader wavelength range, shorter time intervals, pulsed beams, different targets, and new configurations in geometry or external fields. However, what is perhaps not so trivial is to propose experiments for which there is a specific purpose, ... |
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| Doppler-Shifted Reflections of X-Rays in Beam-Foil Spectroscopy, |
1976 |
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| Authors:
E. M. Bernstein; L. C. McIntyre Jr; ARIZONA UNIV TUCSON DEPT OF PHYSICS
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| In a conventional beam-foil spectroscopy experiment, radiation from an ion beam is viewed by a spectrometer after the beam has passed through a thin foil. The plane of the foil is usually perpendicular to the ion beam, and the radiation accepted by the spectrometer is emitted in a small range of angles centered about 90 deg. relative to the beam direction. In order to investigate short-lived atomic states excited by ... |
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| Experimental Limits on the Velocities of Sodium Atoms Sputtered from Solid Surfaces by Hydrogen Ions, |
1976 |
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| Authors:
John O. Stoner Jr; ARIZONA UNIV TUCSON DEPT OF PHYSICS
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| We have observed optical emission at LAMBDA 589.0 nm by sodium atoms sputtered from solid targets by hydrogen molecular ions. We saw no broadening or shifts of this line relative to that from a laboratory lamp, and can therefore put limits upon the speeds of sodium atoms ejected from surfaces in this way. Our results are consistent with the hypothesis that the atomic sodium cloud surrounding Io is produced by ... |
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| Extreme Ultraviolet Spectra of Highly Stripped Silicon Ions, |
1976 |
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| Authors:
P. M. Griffin; D. J. Pegg; I. A. Sellin; K. W. Jones; S. Bashkin; ARIZONA UNIV TUCSON DEPT OF PHYSICS
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| A study of foil-excited spectra in the wavelength range 107-374 A from highly stripped Si ions is reported. Decay-in-flight life-time measurements involving the most prominent and well resolved features will be reported in a future publication. Many of the lines that have been identified are associated with delta n = 0 transitions in Si VI - Si XI of the type 2s(2)2p(k) - 2s2p(k+1) or 2s2p(k) - 2p(k+1). A large ... |
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| Laser Physics, Quantum Optics, Non-Equilibrium Statistical Mechanics and Energy Detectors. |
JUN 1974 |
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| Authors:
Marlan O. Scully; ARIZONA UNIV TUCSON DEPT OF PHYSICS
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| The report contains brief summaries of research conducted in various areas, and abstracts of papers produced under the research program. The unifying concept of the work is non-equilibrium statistical mechanics. Research topics include basic laser theory, laser-phase transition analogy, x ray lasers, experimental quantum optics, Josephson radiation and superconductivity, and coherent phenomena. |
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| Studies in Beam-Foil Spectroscopy. |
NOV 1973 |
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| Authors:
Stanley Bashkin; ARIZONA UNIV TUCSON DEPT OF PHYSICS
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| The report descusses research in beam-foil spectroscopy. Specific illustrations are given of the contributions the project made to the excitation of spectral lines, the construction of energy-level diagrams, the measurements of level mean lives and Lande g-values, production of soft x-rays, Stark and Zeeman effects, applications to astrophysics, technical improvements, and the stimulation of beam-foil and related research in other laboratories. Both experimental and theoretical advances are summarized. (Modified author ... |
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| Quasiparticle Excitations and Photon Pairing in a Radiating Gas. |
01 JAN 1972 |
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| Authors:
T. H. Parmenter; ARIZONA UNIV TUCSON DEPT OF PHYSICS
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| Values of both atomic and photon quasiparticle excitation energies and lifetimes are calculated for the model of a dilute gas of two-level atoms interacting with the electromagnetic modes of a macroscopic enclosure. Interactions both linear and quadratic in the magnetic vector potential are included. Failure to make the rotating wave approximation leads directly to pairing in the system, hole-electron pairing in the atoms, photon-photon pairing in the electromagnetic modes. The ... |
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| On the Possibility of High Precision Beam-Foil Spectroscopy Using a Modified Lamb-Dip Technique, |
1972 |
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| Authors:
W. Chow; A. D. Maio; M. O. Scully; ARIZONA UNIV TUCSON DEPT OF PHYSICS
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| The application of beam-foil techniques to high precision atomic physics is complicated by dispersion in the atomic velocities. This is analogous to the thermal Doppler broadening found in conventional laboratory sources. The advent of stable high-intensity laser sources has led to saturation (Lamb-dip) spectroscopy, which enables measurement eigenfrequencies and natural lifetimes independent of the Doppler width. The application of this idea to beam-foil experiments involves two (tunable) laser sources. A ... |
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| Research in Theoretical Quantum Optics. |
SEP 1971 |
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| Authors:
Marlan O. Scully; ARIZONA UNIV TUCSON DEPT OF PHYSICS
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| During the course of AFOSR Contract no. 70-1921 several problems were solved, seven papers were published and substantial progress was made on still other fronts. The areas of research involved include: the detection and emission of coherent infrared radiation by superconducting tunnel junctions (papers 1 and 2), aspects of coherence theory including the revelation of outstanding problems in the quantum theory of laser radiation (papers 3 and 4), the completion ... |
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| Measurement of g-Factors for Levels in Ne II, III. |
12 MAY 1971 |
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| Authors:
C. H. Liu; D. A. Church; ARIZONA UNIV TUCSON DEPT OF PHYSICS
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| The alignment of the radiating particles in the beam-foil light source has been used to measure the Lande g-factors of excited electronic states of 20Ne II, III with lifetimes of the order of nanoseconds. (Author) |
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| Operation of Van de Graaff Accelerators for Basic Experiments in Atomic Spectroscopy. |
JAN 1971 |
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| Authors:
Stanley Bashkin; ARIZONA UNIV TUCSON DEPT OF PHYSICS
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| A brief summary is given of studies in the field of beam-foil spectroscopy. The research related to the measurement of transition energies in atoms and ions, and the mean lives and quantum numbers associated with excited electronic levels. Much of the work was devoted to structure of multiply-ionized systems. The report includes a list of all published papers and the names of all people associated with work under the contract. ... |
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| Persistent Currents in the Excitonic Insulator. |
21 DEC 1970 |
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| Authors:
W. R. Henson; R. H. Parmenter; ARIZONA UNIV TUCSON DEPT OF PHYSICS
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| The energy gap is solved for the excitonic insulator in the presence of persistent currents. In the zero temperature case, an analytical solution is found, while numerical solutions are found for finite temperatures. It is shown that the solutions vary only slightly as the hole-electron mass difference is varied. Critical currents, corresponding to a first-order transition back to the normal phase, are found numerically. (Author) |
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| Accurate Pairing Treatment of the Coulomb Interaction in the Anderson Model of a Localized Moment in a Metal. |
21 DEC 1970 |
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| Authors:
R. H. Parmenter; ARIZONA UNIV TUCSON DEPT OF PHYSICS
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| The treatment of the Anderson model of a localized moment in a metal has been extended beyond the effective-field approximation by a method recently developed for studying the Hubbard model. This leads to an accurate treatment of the Coulomb interaction associated with the localized center. The results are a simple generalization of those obtained by Anderson within the context of the effective-field approximation. (Author) |
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| TREATMENT OF PAIRING IN MANY-BODY SYSTEMS BY AN EQUATION-OF-MOTION METHOD. |
21 NOV 1969 |
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| Authors:
R. H. Parmenter; ARIZONA UNIV TUCSON DEPT OF PHYSICS; ARIZONA UNIV TUCSON DEPT OF PHYSICS
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| A completely unambiguous prescription is presented for extending the equation-of-motion method, including pairing, beyond the random-phase approximation. When combined with the idea of a generalized effective field, this prescription leads to a simple, self-consistent treatment of pairing, lifetime, and renormalization effects in many-body systems. (Author) |
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| PAIRING TREATMENT OF INTERACTING LOCALIZED MOMENTS IN DILUTE MAGNETIC ALLOYS. |
21 NOV 1969 |
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| Authors:
R. H. Parmenter; ARIZONA UNIV TUCSON DEPT OF PHYSICS; ARIZONA UNIV TUCSON DEPT OF PHYSICS
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| The Anderson model of a localized magnetic center is used to study a system of interacting localized moments in a dilute magnetic alloy. The effective interaction between centers, mediated by the conduction electrons, causes the localized quasiparticle energies to spread and lower by an amount proportional to the square root of n sub 0 (n sub 0 being the density of centers). The proportionality factor is greater, by ... |
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| PHYSICAL PROPERTIES OF SOLIDS AT HIGH PRESSURES. |
APR 1968 |
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| Authors:
Carl T. Tomizuka; ARIZONA UNIV TUCSON DEPT OF PHYSICS
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| The pressure effect study on the self-diffusion rate in noble metals is completed to yield the activation volume for this process. The effect of pressure on the resistivity of nickel and nickel-copper alloys yielded the theoretically significant information regarding the shift in the s-d band overlap as a function of the interatomic distance. Pressure effect on the magnetic properties of palladium-cobalt alloy and compounds gadolinium-gold and gadolinium-copper yields results of ... |
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