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Measurement of CP Violation in B0 to Phi K0, and of Branching Fraction and CP Violation in B0 to F0(980) K0(S)

Description: The authors measure the time-dependent CP asymmetry parameters in B{sup 0} {yields} K{sup +}K{sup -}K{sup 0} based on a data sample of approximately 277 million B-meson pairs recorded at the {Upsilon}(4S) resonance with the BABAR detector at the PEP-II B-meson Factory at SLAC. They reconstruct two-body B{sup 0} decays to {phi}(1020)K{sub s}{sup 0} and {phi}(1020)K{sub L}{sup 0}. Using a time-dependent maximum-likelihood fit, they measure sin2{beta}{sub eff}({phi}K{sup 0}) = 0.48 {+-} 0.28 {+-} … more
Date: March 10, 2008
Creator: Kutter, Paul E.
Partner: UNT Libraries Government Documents Department
open access

Dalitz Analysis of D0 to K0(S) Pi+ Pi- and Measurement of the CKM Angle Gamma in Charged B+- Decays to D(*) K+- Decays

Description: Despite more than thirty years having elapsed since the discovery of CP violation, our understanding about the source and the nature of this phenomenon is still very limited. In the standard model of particle physics, CP violation is due to the presence of an non-irreducible weak phase in the Cabibbo-Kabayashi-Maskawa(CKM) matrix. Up to now, all the experimental results are in good agreement with the standard model. However, it is important for us to over-constrain the CKM quark-mixing matrix a… more
Date: July 10, 2007
Creator: Lau, Yan-Pan
Partner: UNT Libraries Government Documents Department
open access

The relationship of structure to superconductivity in the Pr-Ba-Cu-O system

Description: The relation of structure to lack of superconductivity in Pr-Ba-Cu-O was systematically investigated. First, the phase equilibria of this system was studied to find the processing parameters which maximize the cation-site ordering between Pr and Ba ions. Second, a comparative study between superconducting Nd-Ba-Cu-0 and non- superconducting Pr-Ba-Cu-0 was performed by forming solid-solution Nd- Pr-Ba-Cu-0. The relation between structure and superconductivity in Nd{sub 1{minus}x}Pr{sub x}Ba{sub … more
Date: May 10, 1994
Creator: Minseo, P.
Partner: UNT Libraries Government Documents Department
open access

Thermochemical decomposition and isomerization of polysilacyclodialkynes and thermochemical and photochemical decomposition of cyclopolysilylketenes

Description: Kinetic data for elimination of silylene supports formation of a ``tighter`` transition state, indicating a silacyclopropene intermediate. This extends the silacyclopropene mechanism to the cyclicdialkyne system and validates the consistency of the mechanism for silylakynes, in general. Investigation into the other possible silacyclopropene product established the instability of the product. The work with silylketenes proved that an inherent difference exists between reactivity of monosilyl-sub… more
Date: May 10, 1994
Creator: Altman, L. B.
Partner: UNT Libraries Government Documents Department
open access

Diffusion of adatoms on face-centered cubic transition metal surfaces

Description: Mechanisms and associated energetics for adatom diffusion on the (100) and (110) surfaces of Ni, Cu, Rh, Pd, and Ag are investigated. Self-diffusion was studied on (100) and (I 10) surfaces of Ni, Cu, Pd and Ag using corrected effective medium method (CEM) and approximation to CEM used for molecular dynamics and Monte Carlo studies (MD/MC-CEM). Self-diffusion on Pd(100), Ag(100), Ni(110), Cu(110), Pd(110), and Ag(110) is accomplished by classical diffusion: the adatom hops from its equilibrium … more
Date: May 10, 1994
Creator: Perkins, L.
Partner: UNT Libraries Government Documents Department
open access

Interactions of hydrogen with alkali promoted Ru/SiO{sub 2} catalysts: A proton NMR study

Description: Role of H spillover to the silica support was studied using chemisorption; a strongly bound component of spilled over H was found in the silica support which interfered with accurate measurements of active metal sites via volumetric strong H chemisorption. The volumetric chemisorption technique was modified so that measurement times were reduced from 12--36 h to 1 h. The active Ru surface was characterized means of changes in proton spin counts and NMR Knight shifts vs alkali loading. Na, K blo… more
Date: May 10, 1994
Creator: Ozbay, U. D.
Partner: UNT Libraries Government Documents Department
open access

Microfabrication of an Implantable silicone Microelectrode array for an epiretinal prosthesis

Description: Millions of people suffering from diseases such as retinitis pigmentosa and macular degeneration are legally blind due to the loss of photoreceptor function. Fortunately a large percentage of the neural cells connected to the photoreceptors remain viable, and electrical stimulation of these cells has been shown to result in visual perception. These findings have generated worldwide efforts to develop a retinal prosthesis device, with the hope of restoring vision. Advances in microfabrication, i… more
Date: June 10, 2003
Creator: Maghribi, M
Partner: UNT Libraries Government Documents Department
open access

Error Detection, Factorization and Correction for Multi-View Scene Reconstruction from Aerial Imagery

Description: Scene reconstruction from video sequences has become a prominent computer vision research area in recent years, due to its large number of applications in fields such as security, robotics and virtual reality. Despite recent progress in this field, there are still a number of issues that manifest as incomplete, incorrect or computationally-expensive reconstructions. The engine behind achieving reconstruction is the matching of features between images, where common conditions such as occlusions,… more
Date: November 10, 2011
Creator: Hess-Flores, M.
Partner: UNT Libraries Government Documents Department
open access

A Measurement of the Rate of Muon Capture in Hydrogen Gas andDetermination of the Proton's Induced Pseudoscalar Coupling gP

Description: This dissertation describes a measurement of the rate ofnuclear muon capture by the proton, performed by the MuCap Collaborationusing a new technique based on a time projection chamber operating inultraclean, deuterium-depleted hydrogen gas at room temperature and 1 MPapressure. The hydrogen target's low gas density of 1 percent compared toliquid hydrogen is key to avoiding uncertainties that arise from theformation of muonic molecules. The capture rate was obtained from thedifference between t… more
Date: July 10, 2007
Creator: Banks, Thomas Ira
Partner: UNT Libraries Government Documents Department
open access

Measurement of Branching Fractions and CP-Violating Asymmetries in B0 to K0K0bar and B+ to K0barK+ Decays at the BaBar Experiment

Description: Over the last few years, the B factories have established the Cabbibo-Kobayashi-Maskawa mechanism of CP violation in the Standard Model through the study of the decays of B mesons. The focus of Belle and BaBar has now expanded to the search for signatures of new physics beyond the Standard Model, particularly through examination of flavor-changing neutral-current transitions, which proceed through diagrams involving virtual loops. These decays are suppressed in the Standard Model, increasing se… more
Date: July 10, 2007
Creator: Biesiada, Jedrzej
Partner: UNT Libraries Government Documents Department
open access

DECAY PROPERTIES OF THE E HYPERON AND E RESONANCES

Description: A sample of 2500 {Xi}{sup -} and 500 {Xi}{sup 0} hyperons, produced in {Xi}K, {Xi}K{pi}, and {Xi}K{pi}{pi} final states by K{sup -} (in H{sub 2}) at incident momenta of 1.7 to 2.7 BeV/c, has been analyzed. The data are from an exposure (K-63) of 26 events/{mu}b in the 72-inch bubble chamber; approximately 85% of the {Xi}{sup -} events and 60% of the {Xi}{sup 0} events have been analyzed. For the {Xi}, they determine the spin and decay parameters a{sub {Xi}} and {Phi}{sub {Xi}} = tan{sup -1} ({b… more
Date: September 10, 1966
Creator: Merrill, Jr., Deane W.
Partner: UNT Libraries Government Documents Department
open access

The Higgs boson in the Standard Model theoretical constraints and a direct search in the wh channel at the Tevatron

Description: We have presented results in two different yet strongly linked aspects of Higgs boson physics. We have learned about the importance of the Higgs boson for the fate of the Standard Model, being either only a theory limited to explaining phenomena at the electroweak scale or, if the Higgs boson lies within a mass range of 130 &lt; m<sub>H</sub> &lt; 160 GeV the SM would remain a self consistent theory up to highest energy scales O(m<sub>Pl</sub>). This could have direct implications on theories o… more
Date: September 10, 2010
Creator: Huske, Nils Kristian & (Germany)], Bielefeld Univ.
Partner: UNT Libraries Government Documents Department
open access

The Fluidized Condenser

Description: No Description Available.
Date: May 10, 1952
Creator: Beck, Curt B.; Canby, Thomas D. & Zonis, Irwin S.
Partner: UNT Libraries Government Documents Department
open access

Evidence for neutrino oscillations in the Sudbury Neutrino Observatory

Description: The Sudbury Neutrino Observatory (SNO) is a large-volume heavy water Cerenkov detector designed to resolve the solar neutrino problem. SNO observes charged-current interactions with electron neutrinos, neutral-current interactions with all active neutrinos, and elastic-scattering interactions primarily with electron neutrinos with some sensitivity to other flavors. This dissertation presents an analysis of the solar neutrino flux observed in SNO in the second phase of operation, while {approx}2… more
Date: August 10, 2004
Creator: Marino, Alysia Diane
Partner: UNT Libraries Government Documents Department
open access

Geometry, topology, and string theory

Description: A variety of scenarios are considered which shed light upon the uses and limitations of classical geometric and topological notions in string theory. The primary focus is on situations in which D-brane or string probes of a given classical space-time see the geometry quite differently than one might naively expect. In particular, situations in which extra dimensions, non-commutative geometries as well as other non-local structures emerge are explored in detail. Further, a preliminary exploratio… more
Date: July 10, 2003
Creator: Varadarajan, Uday
Partner: UNT Libraries Government Documents Department
open access

Structural studies of conformational changes of proteins upon phosphorylation: Structures of activated CheY, CheY-N16-FliM complex, and AAA {sup +} ATPase domain of NtrC1 in both inactive and active states

Description: Protein phosphorylation is a general mechanism for signal transduction as well as regulation of cellular function. Unlike phosphorylation in eukaryotic systems that uses Ser/Thr for the sites of modification, two-component signal transduction systems, which are prevalent in bacteria, archea, and lower eukaryotes, use an aspartate as the site of phosphorylation. Two-component systems comprise a histidine kinase and a receiver domain. The conformational change of the receiver domain upon phosphor… more
Date: April 10, 2003
Creator: Lee, Seok-Yong
Partner: UNT Libraries Government Documents Department
open access

Maskless, resistless ion beam lithography

Description: As the dimensions of semiconductor devices are scaled down, in order to achieve higher levels of integration, optical lithography will no longer be sufficient for the needs of the semiconductor industry. Alternative next-generation lithography (NGL) approaches, such as extreme ultra-violet (EUV), X-ray, electron-beam, and ion projection lithography face some challenging issues with complicated mask technology and low throughput. Among the four major alternative NGL approaches, ion beam lithogra… more
Date: March 10, 2003
Creator: Ji, Qing
Partner: UNT Libraries Government Documents Department
open access

A semi-experimental nodal synthesis method for the on-line reconstruction of three-dimensional neutron flux-shapes and reactivity. Final report

Description: The safety and optimal performance of large, commercial, light-water reactors require the knowledge at all time of the neutron-flux distribution in the core. In principle, this information can be obtained by solving the time-dependent neutron diffusion equations. However, this approach is complicated and very expensive. Sufficiently accurate, real-time calculations (time scale of approximately one second) are not yet possible on desktop computers, even with fast-running, nodal kinetics codes. A… more
Date: December 10, 1991
Creator: Jacqmin, Robert P.
Partner: UNT Libraries Government Documents Department
open access

Characterizing the Material Properties of Polymer-Based Microelectrode Arrays for Retinal Prosthesis

Description: The Retinal Prosthesis project is a three year project conducted in part at the Lawrence Livermore National Laboratory and funded by the Department of Energy to create an epiretinal microelectrode array for stimulating retinal cells. The implant must be flexible to conform to the retina, robust to sustain handling during fabrication and implantation, and biocompatible to withstand physiological conditions within the eye. Using poly(dimethyl siloxane) (PDMS), LLNL aims to use microfabrication te… more
Date: May 10, 2003
Creator: Park, C S & Maghribi, M
Partner: UNT Libraries Government Documents Department
open access

High Temperature coatings based on {beta}-NiAI

Description: High temperature alloys are reviewed, focusing on current superalloys and their coatings. The synthesis, characerization, and oxidation performance of a NiAl–TiB{sub 2} composite are explained. A novel coating process for Mo–Ni–Al alloys for improved oxidation performance is examined. The cyclic oxidation performance of coated and uncoated Mo–Ni–Al alloys is discussed.
Date: July 10, 2012
Creator: Severs, Kevin
Partner: UNT Libraries Government Documents Department
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