Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Discipline
- Keyword
-
- Boltzmann equation (1)
- Complementarity (1)
- Condensation (1)
- Depolarization spectra (1)
- Forward scattering (1)
-
- Frequency spectra (1)
- Galvanized steel (1)
- Graphite (1)
- Gross equation (1)
- Hyperfine structure (1)
- Intermetallic compunds (1)
- Krypton (1)
- Lippmann Schwinger equation (1)
- Magnesium (1)
- Matrix derivatives (1)
- Mesons (1)
- Nuclear track detectors (1)
- Pions (1)
- Polarization interference spectroscopy (1)
- Polarization spectroscopy (1)
- Quantum theory (1)
- Quark models (1)
- Rare gas (1)
Articles 1 - 9 of 9
Full-Text Articles in Physical Sciences and Mathematics
A Relativistic Model For Heavy Mesons, Jialin Zeng
A Relativistic Model For Heavy Mesons, Jialin Zeng
Physics Theses & Dissertations
Motivated by the present interest in the heavy quark effective theory, we construct a model for heavy mesons based on a relativistic bound state wave equation, the Gross equation. The kernel we use is based on scalar confining and vector Coulomb potentials. Wave functions are treated to leading order and energies to order 1/MQ in the heavy-light systems, and to order 1/M2Q in heavy-heavy systems. Our results are in good agreement with experimental measurements. This model may be used to study weak decay properties in the framework of the heavy quark effective theory and ultimately to …
Heavy-Ion Interaction Models For Radiation Transport, Rajendra R. Dubey
Heavy-Ion Interaction Models For Radiation Transport, Rajendra R. Dubey
Physics Theses & Dissertations
This dissertation is concerned with finding the values for the nuclear cross sections used in the Boltzmann equation for space radiation transport and dose estimates. An extraordinary number of cross sections are required because of the large number of ion types and their extensive energy range, The Lippmann-Schwinger equation is numerically solved in momentum space for a first order optical potential (free space case) and calculations are made for the total and absorption cross sections for nudeus-nucleus scattering. Absorption cross sections are also calculated using a medium modified firstorder optical potential in the Lippmann-Schwinger equation and are compared with experimental …
The Study Of Pion Absorption On -4he At 355 Mev/C With Lads (Large Acceptance Detector System), Thomas A. Dooling
The Study Of Pion Absorption On -4he At 355 Mev/C With Lads (Large Acceptance Detector System), Thomas A. Dooling
Physics Theses & Dissertations
The medium and long range part of the nucleon-nucleon interaction can be described within the framework of pion exchange. In order to understand this fundamental interaction, it is therefore important to study the interaction of pions with nucleons and nuclei, which can either be elastic or inelastic scattering or absorption. Whereas the elastic and inelastic channels can be well described by different models, our understanding of pion absorption is still rather poor. There are still a lot of open questions, for instance on the strength of three and more nucleon absorption and the role of initial and final state interactions. …
Nuclear Forward-Scattering Of Synchrotron Radiation From Krypton: First Observation And Application To The Study Of Lattice Dynamics In Near-Monolayer Krypton-On-Graphite, David Eric Johnson
Nuclear Forward-Scattering Of Synchrotron Radiation From Krypton: First Observation And Application To The Study Of Lattice Dynamics In Near-Monolayer Krypton-On-Graphite, David Eric Johnson
Physics Theses & Dissertations
Since 1985 nuclear-resonant scattering, and in particular nuclear forward-scattering, of synchrotron radiation has been observed in a select few Mossbauer isotopes including: 57Fe, 119Sn, 169Tm. For the first time, nuclear forward-scattering from the 9.4 keV Mossbauer level in 83Kr has been observed. A large resonance effect, comparable to that in 57Fe, has been observed in a variety of systems containing Kr including bulk crystals and physisorbed Kr-on-exfoliated graphite. Previous nuclear-resonant scattering experiments using synchrotron radiation have consisted of demonstration experiments. Nuclear forward-scattering from Kr has been applied to study the lattice dynamics of near-monolayer Kr-on-graphite …
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 …
Identification And Characterization Of The Iron-Zinc Intermetallics Formed In Galvanneal Steel, Richard Frederick George Grant
Identification And Characterization Of The Iron-Zinc Intermetallics Formed In Galvanneal Steel, Richard Frederick George Grant
Physics Theses & Dissertations
The demand to improve the corrosion resistance of steel sheet, particularly for use within the automotive industry, has led to a dramatic increase in the use of coated steels in place of cold-rolled sheet steel. Galvanneal steel results from the post annealing of the zinc-coated steel sheet, in which iron and zinc are interdiffused to form an iron-zinc alloy coating. Within this alloy coating, four main iron-zinc phases, Zeta, Delta, Gamma-1, and Gamma may be present. Manufacture of the most suitable coating requires identifying which phases form during the galvannealing process, an understanding of the properties of each phase and …
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 …
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 …
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. …