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# Physics Commons™

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1994

Dissertations, Theses, and Masters Projects

Discipline

Articles 1 - 8 of 8

## Full-Text Articles in Physics

Glueball Wave Functions And Production Cross Sections, Anthony B. Wakely Jan 1994

#### Glueball Wave Functions And Production Cross Sections, Anthony B. Wakely

##### Dissertations, Theses, and Masters Projects

Three topics are studied in this dissertation.;Using QCD sum rules, I first calculate the first few moments of the distribution amplitude of the pseudoscalar glueball, a bound state of gluons. The distribution amplitude is the momentum wave function integrated over the transverse momentum. QCD sum rules are a method of finding hadronic parameters using perturbative QCD. I use an approximation in which the glueball is treated as a narrow resonance. The moments of the distribution amplitude then give the corresponding first few coefficients of the distribution amplitude for the glueball expanded in Gegenbauer polynomials. The distribution amplitude is rather ...

#### Polarization Transfer Coefficient Measurements In The Deuteron Breakup Reaction Hydrogen-1(Polarized Deuteron,Polarized Proton)X At 2.1 Gev, Naipor Eric Cheung

##### Dissertations, Theses, and Masters Projects

The polarization of the protons emerging at 0$\sp\circ$ from the inclusive deuteron breakup reaction $\sp1$H($\vec d,\vec p$)X was measured using a deuteron beam with kinetic energy of 2.1 GeV. The momentum of the protons was selected by the magnetic spectrometer SPES4 and the polarization was measured with the polarimeter POMME. This experiment was performed at eight different proton momenta. When those momenta are Lorentz transformed to the deuteron rest frame, they corresponded to values from 0.00 to 0.34 GeV/c. The result of the measurements is expressed in terms of polarization ...

Muon Transfer From Muonic Deuterium To Carbon, David William Viel Jan 1994

#### Muon Transfer From Muonic Deuterium To Carbon, David William Viel

##### Dissertations, Theses, and Masters Projects

Negative muons were brought to rest in a gas mixture of 30 torr CH$\sb4$ and 570 torr D$\sb2$, using the cyclotron trap at PSI. The muons formed muonic deuterium atoms which diffused through the mixture and transferred their muons to the carbon of the CH$\sb4$ molecules. A planar germanium detector and a silicon detector were used to observe x-rays from the initial muon cascade in the deuterium, and from subsequent cascade in the muonic carbon after transfer. A transfer rate of (4.5 $\pm$ 1.8) $\times$ 10$\sp{10}$/sec was found which agrees well with ...

Collisions Of Atomic Hydrogen With Oxygen, Sulfur, Sodium And Halogen Anions At Low Energies, James Anthony Fedchak Jan 1994

#### Collisions Of Atomic Hydrogen With Oxygen, Sulfur, Sodium And Halogen Anions At Low Energies, James Anthony Fedchak

##### Dissertations, Theses, and Masters Projects

Total electron detachment and charge transfer cross sections, $\sigma\sb{\rm e}$(E) and $\sigma\sb{\rm ct}$(E), have been measured for collisions of the negative ions O$\sp{-}$, S$\sp{-}$, F$\sp{-}$, Cl$\sp{-}$, Br$\sp{-}$, I$\sp{-}$, Na$\sp{-}$, and K$\sp{-}$ with atomic hydrogen for laboratory energies ranging from 2 to 500 eV. For the systems F$\sp{-}$, Cl$\sp{-}$, Br$\sp{-}$, O$\sp{-}$ and S$\sp{-}$ + H, $\sigma\sb{\rm e}$(E) displays no barrier for associative detachment; the results are found to be adequately described by simple curve-crossing models based upon available intermolecular potentials ...

Jan 1994

#### Photoabsorption Spectra Of Hydrogen And Alkali Atoms In Electric Fields, Jing Gao

##### Dissertations, Theses, and Masters Projects

A systematic study of the photoabsorption spectra of highly excited hydrogen and alkali atoms in electric fields is presented, based on the semiclassical closed-orbit theory. In most respects, hydrogen and alkali atoms behave similarly, because the excited alkali atoms have a single electron outside of a small ionic core, and the core only produces small shifts of energy levels and small phase shifts of scattered wave functions.;For hydrogen, the classical motion of the excited electron is regular and closed orbits can be enumerated. Above the zero-field ionization threshold, the system is rather simple. There is only one closed orbit ...

Jan 1994

#### A Relativistic Model Of Pion Nucleon Scattering And Pion Photoproduction On A Single Nucleon, Yohanes Surya

##### Dissertations, Theses, and Masters Projects

Pion nucleon scattering is described by a manifestly covariant wave equation in which the pion is restricted to its mass-shell. The kernel of the equation includes nucleon (N), Roper (N*), delta ({dollar}\Delta{dollar}) and {dollar}D\sb{lcub}13{rcub}{dollar} poles, with their corresponding crossed pole terms approximated by contact interactions, and contact {dollar}\sigma{dollar}- and {dollar}\rho{dollar}-like exchange terms. The {dollar}\pi NN{dollar} vertex is treated as a mixture of {dollar}\gamma\sp5{dollar} and {dollar}\gamma\sp\mu\gamma\sp5{dollar} coupling, with a mixing parameter {dollar}\lambda{dollar} chosen so that ...

Low Internal Magnetic Fields In Anisotropic Superconductors, Allan J. Greer Jr. Jan 1994

#### Low Internal Magnetic Fields In Anisotropic Superconductors, Allan J. Greer Jr.

##### Dissertations, Theses, and Masters Projects

This thesis is a theoretical, numerical study of the magnetic fields which exist in the anisotropic, high temperature superconductors like $YBa\sb2Cu\sb3O\sb{7-\delta}$, or YBCO for short, using both the anisotropic London theory and simulations based on existing muon spin rotation techniques. The thesis first describes the muon spin rotation ($\mu$SR) techniques, and then gives a brief discussion of superconductivity with regard to the London theory of anisotropic, type II superconductors. Next, numerical results of the application of this theory to YBCO are presented. Three dimensional surface plots of the magnetic field components within the flux ...

Jan 1994

#### Models For Water Outgassing From Metal Surfaces, Minxu Li

##### Dissertations, Theses, and Masters Projects

In this study, the outgassing rate from an electropolished stainless steel surface following exposures to H{dollar}\sb2{dollar}O vapor under various conditions was measured. The results of the experiments showed that the outgassing rate is proportional to {dollar}p\sb0\sp{lcub}n{rcub}{dollar}, where {dollar}p\sb0{dollar} is the H{dollar}\sb2{dollar}O exposure pressure and n is about 0.25. The outgassing rate is not as strongly dependent on the system temperature as one would expect if the temperature is kept the same during exposure and pump-down. The outgassing rate is also a ...