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The neutron electric form factor to Q² = 1.45 (GeV/c)²

Description: The nucleon elastic electromagnetic form factors are fundamental quantities needed for an understanding of nucleon and nuclear electromagnetic structure. The evolution of the Sachs electric and magnetic form factors with Q2, the square of the four-momentum transfer, is related to the distribution of charge and magnetization within the nucleon. High precision measurements of the nucleon form factors are essential for stringent tests of our current theoretical understanding of confinement within … more
Date: February 1, 2004
Creator: Plaster, Bradley
Partner: UNT Libraries Government Documents Department
open access

Search for the Standard Model Higgs Boson in the $WH \to \ell \nu b\bar{b}$ Channel in 1.96-TeV Proton-Antiproton Collisions

Description: We have searched for the Standard Model Higgs boson in the WH → lvbb channel in 1.96 TeV pp collisions at CDF. This search is based on the data collected by March 2009, corresponding to an integrated luminosity of 4.3 fb<sup>-1</sup>. The W H channel is one of the most promising channels for the Higgs boson search at Tevatron in the low Higgs boson mass region.
Date: February 1, 2010
Creator: Nagai, Yoshikazu
Partner: UNT Libraries Government Documents Department
open access

Catalytic Conversion of Solvent Refined Coal to Liquid Products

Description: Catalytic reactions of solvent refined coal (SRC) were studied using mixed metal oxide and low melting Lewis acid catalysts in extracting solvent media. From characterization of the benzene- and cyclohexane-soluble products, ZnCl/sub 2/ and SnCl/sub 2/ were determined to be the most effective at hydrogenating and solubilizing SRC while assisting in heteroatom removal. ZnCl/sub 2/ and SnCl/sub 2/ were also found to be more effective at producing oil-like products rather than alphaltene-like prod… more
Date: February 1, 1978
Creator: Tanner, K. I. & Bell, A. T.
Partner: UNT Libraries Government Documents Department
open access

Nodal approximations of varying order by energy group for solving the diffusion equation

Description: The neutron flux across the nuclear reactor core is of interest to reactor designers and others. The diffusion equation, an integro-differential equation in space and energy, is commonly used to determine the flux level. However, the solution of a simplified version of this equation when automated is very time consuming. Since the flux level changes with time, in general, this calculation must be made repeatedly. Therefore solution techniques that speed the calculation while maintaining accurac… more
Date: February 1, 1992
Creator: Broda, J. T.
Partner: UNT Libraries Government Documents Department
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Solid state NMR method development and studies of biological and biomimetic nanocomposites

Description: This thesis describes application and development of advanced solid-state nuclear magnetic resonance techniques for complex materials, in particular organic-inorganic nanocomposites and thermoelectric tellurides. The apatite-collagen interface, essential for understanding the biomineralization process in bone and engineering the interface for controlled bio-mimetic synthesis and optimized mechanical properties, is buried within the nanocomposite of bone. We used multinuclear solid-state NMR to … more
Date: February 7, 2011
Creator: Hu, Yanyan
Partner: UNT Libraries Government Documents Department
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Measurement of the B+- Lifetime and Top Quark Identification Using Secondary Vertex B-Tagging

Description: This dissertation presents a preliminary measurement of the B{sup {+-}} lifetime through the full reconstruction of its decay chain, and the identification of top quark production in the electron plus jets channel using the displaced vertex b-tagging method. Its main contribution is the development, implementation and optimization of the Kalman filter algorithm for vertex reconstruction, and of the displaced vertex technique for tagging jets arising from b quark fragmentation, both of which hav… more
Date: February 1, 2004
Creator: Schwartzman, Ariel G. & U., /Buenos Aires
Partner: UNT Libraries Government Documents Department
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Measurement of the Ratio of Inclusive Cross Sections Sigma (p anti-p --> Z + b-jet) / Sigma (p anti-p --> Z + jet) at s**(1/2) = 1.96-TeV

Description: Using the data collected with the D0 detector at {radical}s = 1.96 TeV with integrated luminosities of about 180 pb{sup -1}, we have measured the ratio of inclusive cross sections for p{bar p} {yields} Z + b-jet to p{bar p} {yields} Z + jet production. The inclusive Z + b-jet reaction is an important background to searches for the Higgs boson in associated ZH production at the Fermilab Tevatron collider and is sensitive to the b quark content of the proton. This thesis describes our measurement… more
Date: February 1, 2005
Creator: Mutaf, Yildirim D.
Partner: UNT Libraries Government Documents Department
open access

Measurement of the t anti-t production cross section in p anti-p collisions at s**(1/2) = 1.96-TeV

Description: The direct observation of the top quark was first achieved at the Tevatron proton anti-proton collider at Fermilab. This discovery completed the third generation quark sector where the top quark is expected to accompany the bottom quark in the weak isospin doublet. This dissertation discusses the experimental verification of the production cross section as predicted by the Standard Model. A measurement of the t{bar t} production cross section using 107.9 pb{sup -1} of p{bar p} collisions at {ra… more
Date: February 1, 2004
Creator: Ray, Heather Lynn
Partner: UNT Libraries Government Documents Department
open access

Superconducting High Energy Resolution Gamma-ray Spectrometers

Description: We have demonstrated that a bulk absorber coupled to a TES can serve as a good gamma-ray spectrometer. Our measured energy resolution of 70 eV at 60 keV is among the best measurements in this field. We have also shown excellent agreement between the noise predictions and measured noise. Despite this good result, we noted that our detector design has shortcomings with a low count rate and vulnerabilities with the linearity of energy response. We addressed these issues by implementation of an act… more
Date: February 22, 2002
Creator: Chow, Daniel Tun Lai
Partner: UNT Libraries Government Documents Department
open access

Use of variational techniques for the estimation of neutron detection efficiency

Description: The neutron detection efficiency is a parameter required in the measurement of reactivity by the modified source technique. The direct solution of the detection efficiency at a perturbed state is costly. To solve for this, a particular variational functional, the Lewins' type variational functional, is presented. The functional is a ratio of two other functionals, each dealing with a reaction rate. The evaluation of this particular functional was done by treating the numerator and the denominat… more
Date: February 1, 1976
Creator: Lin, S.; Robinson, J.C. & Flanagan, G.F.
Partner: UNT Libraries Government Documents Department
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The Artisanal Nuke

Description: No Description Available.
Date: February 5, 2014
Creator: Dixon, M C
Partner: UNT Libraries Government Documents Department
open access

Iterative solution of the diffusion and P$sub 1$ finite element equations

Description: A method for obtaining solutions to the time-independent Boltzmann neutron transport equation on triangular grids with nonorthogonal boundaries and anisotropic scattering is developed. A functional is obtained from the canonical form of the multigroup transport equation. The angular variable is then removed by expanding the functional in spherical harmonics, retaining only the first two moments and limiting the anisotropic scattering to be linear. The finite element method is then implemented b… more
Date: February 1, 1976
Creator: Tomlinson, E.T.; Robinson, J.C. & Vondy, D.R.
Partner: UNT Libraries Government Documents Department
open access

THE EFFECT OF THE $sub 4$TENDENCY TO REPORT INJURIES$sub 4$ ON MINOR ACCIDENT STATISTICS: A FOLLOW-UP STUDY

Description: Thesis submitted to Univ. of Tennessee, Knoxville. Statistical methods were used in an attempt to determine the effect of the tendency to report accidents on the systemic variance in minor injury data over a 6-yr period. The population surveyed included 245 journeymen of 9 skilled craft groups continuously employed during the period. Results indicate that injury and non- injury visits to the dispensary were relatively stable during the 6-yr period and that there was a significant positive relat… more
Date: February 1, 1964
Creator: Sergent, J.E.
Partner: UNT Libraries Government Documents Department
open access

Measurement of the top - anti-top Production Cross Section at s**(/1/2) = 1.96-TeV in the e + jets Final State of proton anti-proton Collisions at the Tevatron

Description: We discuss the measurement of the cross section for t{bar t} production in p{bar p} collisions at {radical}s = 1.96 TeV in e+jets final states observed at the D0 experiment at the Fermilab Tevatron. Our result is based on data collected from the June 2002 to September 2003 period of Run II of the p{bar p} Collider. In the Standard Model, the top quark is expected to decay mainly into a W boson and a b quark. The W boson can decay subsequently into a lepton and its neutrino or a q{bar q} quark-a… more
Date: February 1, 2005
Creator: Cho, DooKee
Partner: UNT Libraries Government Documents Department
open access

Two-axis Beam Steering Mirror Control system for Precision Pointing and Tracking Applications

Description: Precision pointing and tracking of laser beams is critical in numerous military and industrial applications. This is particularly true for systems requiring atmospheric beam propagation. Such systems are plagued by environmental influences which cause the optical signal to break up and wander. Example applications include laser communications, precision targeting, active imaging, chemical remote sensing, and laser vibrometry. The goal of this project is to build a beam steering system using a t… more
Date: February 8, 2006
Creator: Ulander, K
Partner: UNT Libraries Government Documents Department
open access

An Experimental Investigation of the Structural Wave Scattering Due to Impedance Discontinuities on a Cylindrical Structure

Description: Experimental, numerical, and analytical work has shown that the response of a shell to a distributed force wave possesses unique characteristics which are dependent on the nature of structure attached to the shell. Specific characteristics which influence the response are the distribution of the discontinuities around the circumference (periodic/aperiodic), the impedance of the discontinuities relative to that of the shell, and the type of impedance (mass or stiffness). Traditional shell theory… more
Date: February 15, 2006
Creator: Glotzbecker, RJ
Partner: UNT Libraries Government Documents Department
open access

Ultrasonic Digital Communication System for a Steel Wall Multipath Channel: Methods and Results

Description: As of the development of this thesis, no commercially available products have been identified for the digital communication of instrumented data across a thick ({approx} 6 n.) steel wall using ultrasound. The specific goal of the current research is to investigate the application of methods for digital communication of instrumented data (i.e., temperature, voltage, etc.) across the wall of a steel pressure vessel. The acoustic transmission of data using ultrasonic transducers prevents the need … more
Date: February 16, 2006
Creator: Murphy, TL
Partner: UNT Libraries Government Documents Department
open access

The Relationships between Weight Functions, Geometric Functions,and Compliance Functions in Linear Elastic Fracture Mechanics

Description: Linear elastic fracture mechanics is widely used in industry because it established simple and explicit relationships between the permissible loading conditions and the critical crack size that is allowed in a structure. Stress intensity factors are the above-mentioned functional expressions that relate load with crack size through geometric functions or weight functions. Compliance functions are to determine the crack/flaw size in a structure when optical inspection is inconvenient. As a resul… more
Date: February 6, 2007
Creator: Yuan, Rong
Partner: UNT Libraries Government Documents Department
open access

Sum-Frequency Generation from Chiral Media and Interfaces

Description: Sum frequency generation (SFG), a second-order nonlinear optical process, is electric-dipole forbidden in systems with inversion symmetry. As a result, it has been used to study chiral media and interfaces, systems intrinsically lacking inversion symmetry. This thesis describes recent progresses in the applications of and new insights into SFG from chiral media and interfaces. SFG from solutions of chiral amino acids is investigated, and a theoretical model explaining the origin and the strengt… more
Date: February 13, 2006
Creator: Ji, Na
Partner: UNT Libraries Government Documents Department
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