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Time-varying Reeb Graphs: A Topological Framework Supporting the Analysis of Continuous Time-varying Data

Description: I present time-varying Reeb graphs as a topological framework to support the analysis of continuous time-varying data. Such data is captured in many studies, including computational fluid dynamics, oceanography, medical imaging, and climate modeling, by measuring physical processes over time, or by modeling and simulating them on a computer. Analysis tools are applied to these data sets by scientists and engineers who seek to understand the underlying physical processes. A popular tool for anal… more
Date: November 28, 2006
Creator: Mascarenhas, A
Partner: UNT Libraries Government Documents Department
open access

Measurement of the Strange Quark Contribution to Proton Structure through Parity Violating Electron-Proton Scattering

Description: The G0 (G-Zero) forward angle experiment completed in Hall C of the Thomas Jefferson National Accelerator Facility (TJNAF) has measured the parity violating asymmetries in elastic electron-proton scattering over a Q2 range of 0.12 < Q2 < 1.0 (GeV/c)2. A linear combination of the strange electric (GsE) and magnetic (GsM) form factors calculated from these asymmetries indicate a non-zero contribution of the strange quark to the charge and magnetization structure of the proton in the above kinemat… more
Date: May 1, 2006
Creator: Nakahara, Kazutaka
Partner: UNT Libraries Government Documents Department
open access

Measurement of the t-tbar production cross section in p-pbar collisions at s**(1/2) = 1.96 TeV using lepton+jets events in the CDF detector at Fermilab

Description: The top quark is the most massive fundamental particle observed so far, and the study of its properties is interesting for several reasons ranging from its possible special role in electroweak symmetry breaking to its sensitivity to physics beyond the standard model (SM). In particular, the measurement of the top quark pair production cross section {sigma}{sub t{bar t}} is of interest as a test of QCD predictions. Recent QCD calculations done with perturbation theory to next-to-leading order pr… more
Date: December 1, 2006
Creator: Palencia, Enrique
Partner: UNT Libraries Government Documents Department
open access

Measurements of the B Production Cross Section in Proton-Antiproton Collisions at s**(1/2) = 1.96 TeV using semileptonic decays of b hadrons

Description: The authors present a measurement of the cross section of b hadron (H{sub b}) production in p{bar p} collisions at {radical}s = 1.96 TeV using the CDF II detector at the Fermilab Tevatron. They use 83 pb{sup -1} of data taken between october 2002 and May 2003 that was collected with a trigger sensitive to high momentum muons and displaced tracks. They use partially reconstructed decays in the following modes: H{sub b} {yields} {mu}{sup -} {bar {nu}}{sub {mu}}D{sup 0}X, D{sup 0} {yields} K{sup -… more
Date: July 1, 2006
Creator: Kraus, James Alexander
Partner: UNT Libraries Government Documents Department
open access

Novel Aryne Chemistry in Organic Synthesis

Description: Arynes are among the most intensively studied systems in chemistry. However, many aspects of the chemistry of these reactive intermediates are not well understood yet and their use as reagents in synthetic organic chemistry has been somewhat limited, due to the harsh conditions needed to generate arynes and the often uncontrolled reactivity exhibited by these species. Recently, o-silylaryl triflates, which can generate the corresponding arynes under very mild reaction conditions, have been foun… more
Date: December 12, 2006
Creator: Liu, Zhijian
Partner: UNT Libraries Government Documents Department
open access

Search for 3rd Generation Vector Leptoquarks in the Di-tau Di-jet Channel in Proton Antiproton Collisions at square root s = 1.96 TeV

Description: We search for third generation vector leptoquarks (V LQ3) produced in colliding p{bar p} beams operating at {radical}s = 1.96 TeV at the CDF experiment in Run II of the Fermilab Tevatron. We use 322 pb{sup -1} of data to search for the V LQ3 signal in the di-tau plus di-jet channel. For the first time, the full matrix element is used in the Monte Carlo simulation of this signal. With no events observed in the signal region, we set a 95% C.L. upper limit on the V LQ3 pair production cross sectio… more
Date: December 1, 2006
Creator: Forrester, Stanley Scott
Partner: UNT Libraries Government Documents Department
open access

Search for t-Channel Single Top Quark Production in p anti-p Collisions at 1.96 TeV

Description: I have performed a search for t-channel single top quark production in p{bar p} collisions at 1.96 TeV on a 366 pb{sup -1} dataset collected with the D0 detector from 2002-2005. The analysis is restricted to the leptonic decay of the W boson from the top quark to an electron or muon, tq{bar b} {yields} lv{sub l}b q{bar b} (l = e,{mu}). A powerful b-quark tagging algorithm derived from neural networks is used to identify b jets and significantly reduce background. I further use neural networks t… more
Date: June 1, 2006
Creator: Perea, Philip Michael & /UC, Riverside
Partner: UNT Libraries Government Documents Department
open access

SEARCH FOR HIGH-MASS RESONANCES DECAYING TO e-mu IN ppbar COLLISIONS AT s**(1/2) = 1.96 TeV

Description: We describe a general search for resonances decaying to a neutral e{mu} final state in p{bar p} collisions at a center-of-mass energy of 1.96 TeV. Using a data sample representing 344 pb{sup -1} of integrated luminosity recorded by the CDF II experiment, we compare Standard Model predictions with the number of observed events for invariant masses between 50 and 800 GeV/c{sup 2}. Finding no significant excess (5 events observed vs. 7.7 {+-} 0.8 expected for M{sub e{mu}} &gt; 100 GeV/c{sup 2}), w… more
Date: August 1, 2006
Creator: Hahn, Kristian Allan
Partner: UNT Libraries Government Documents Department
open access

Heat Transfer Analysis and Assessment of Kinetics Systems for PBX 9501

Description: The study of thermal decomposition in high explosive (HE) charges has been an ongoing process since the early 1900s. This work is specifically directed towards the analysis of PBX 9501. In the early 1970s, Dwight Jaeger of Los Alamos National Laboratory (LANL) developed a single-step, two-species kinetics system that was used in the development of one of the first finite element codes for thermal analyses known as EXPLO. Jaeger's research focused on unconfined spherical samples of HE charges to… more
Date: July 31, 2006
Creator: Jorenby, Jeffrey W.
Partner: UNT Libraries Government Documents Department
open access

A measurement of the top quark mass with a matrix element method

Description: The authors present a measurement of the mass of the top quark. The event sample is selected from proton-antiproton collisions, at 1.96 TeV center-of-mass energy, observed with the CDF detector at Fermilab's Tevatron. They consider a 318 pb{sup -1} dataset collected between March 2002 and August 2004. They select events that contain one energetic lepton, large missing transverse energy, exactly four energetic jets, and at least one displaced vertex b tag. The analysis uses leading-order t{bar t… more
Date: December 1, 2006
Creator: Gibson, Adam Paul
Partner: UNT Libraries Government Documents Department
open access

Under-sampling in a Multiple-Channel Laser Vibrometry System

Description: Laser vibrometry is a technique used to detect vibrations on objects using the interference of coherent light with itself. Most vibrometry systems process only one target location at a time, but processing multiple locations simultaneously provides improved detection capabilities. Traditional laser vibrometry systems employ oversampling to sample the incoming modulated-light signal, however as the number of channels increases in these systems, certain issues arise such a higher computational co… more
Date: August 15, 2006
Creator: Corey, J
Partner: UNT Libraries Government Documents Department
open access

Genotyping and Bioforensics of Ricinus communis

Description: The castor bean plant (Ricinus communis) is a member of the family Euphorbiaceae. In spite of its common name, the castor plant is not a true bean (i.e., leguminous plants belonging to the family, Fabaceae). Ricinus communis is native to tropical Africa, but because the plant was recognized for its production of oil with many desirable properties, it has been introduced and cultivated in warm temperate regions throughout the world (Armstrong 1999 and Brown 2005). Castor bean plants have also be… more
Date: November 20, 2006
Creator: Hinckley, A C
Partner: UNT Libraries Government Documents Department
open access

High Pressure Scanning Tunneling Microscopy and High PressureX-ray Photoemission Spectroscopy Studies of Adsorbate Structure,Composition and Mobility during Catalytic Reactions on A Model SingleCrystal

Description: Our research focuses on taking advantage of the ability of scanning tunneling microscopy (STM) to operate at high-temperatures and high-pressures while still providing real-time atomic resolution images. We also utilize high-pressure x-ray photoelectron spectroscopy (HPXPS) to monitor systems under identical conditions thus giving us chemical information to compare and contrast with the structural and dynamic data provided by STM.
Date: May 12, 2006
Creator: Montano, M. O.
Partner: UNT Libraries Government Documents Department
open access

Understanding How Femtosecond Laser Waveguide Fabrication in Glasses Works

Description: In order to understand the physical processes associated with fs-laser waveguide writing in glass, the effects of the laser repetition rate, the material composition and feature size were studied. The resulting material changes were observed by collecting Raman and fluorescence spectra with a confocal microscope. The guiding behavior of the waveguides was evaluated by measuring near field laser coupling profiles in combination with white light microscopy. Waveguides and Bragg gratings were fabr… more
Date: May 11, 2006
Creator: Reichman, W J
Partner: UNT Libraries Government Documents Department
open access

Search for r-parity violating supersymmetry in multilepton final states with the D0 detector

Description: Results obtained from a search for the trilepton signature {mu}{mu}{ell} (with {ell} = e, or {mu}) are combined with two complementary searches for the trilepton signatures ee{ell} and eer and interpreted in the framework of R-parity violating Supersymmetry. Pairwise, R-parity conserving production of the supersymmetric particles is assumed, followed by R-parity violating decays via an LL{bar E}-operator with one dominant coupling {lambda}{sub 122}. An LL{bar E}-operator couples two weak isospi… more
Date: November 1, 2006
Creator: Kaefer, Daniela
Partner: UNT Libraries Government Documents Department
open access

Measurement of the front back asymmetry in top-antitop quark pairs produced in proton-antiproton collisions at center of mass energy = 1.96 TeV

Description: Quarks, along with leptons and force carrying particles, are predicted by the Standard Model to be the fundamental constituents of nature. In distinction from the leptons, the quarks interact strongly through the chromodynamic force and are bound together within the hadrons. The familiar proton and neutron are bound states of the light ''up'' and ''down'' quarks. The most massive quark by far, the ''top'' quark, was discovered by the CDF and D0 experiments in March, 1995. The new quark was obse… more
Date: January 1, 2006
Creator: Schwarz, Thomas A.
Partner: UNT Libraries Government Documents Department
open access

Structure, ionic Conductivity and mobile Carrier Density in Fast Ionic Conducting Chalcogenide Glasses

Description: This thesis consists of six sections. The first section gives the basic research background on the ionic conduction mechanism in glass, polarization in the glass, and the method of determining the mobile carrier density in glass. The proposed work is also included in this section. The second section is a paper that characterizes the structure of MI + M{sub 2}S + (0.1 Ga{sub 2}S{sub 3} + 0.9 GeS{sub 2}) (M = Li, Na, K and Cs) glasses using Raman and IR spectroscopy. Since the ionic radius plays … more
Date: December 12, 2006
Creator: Yao, Wenlong
Partner: UNT Libraries Government Documents Department
open access

First search at CDF for the Higgs boson decaying to a W-boson pair in proton-antiproton collisions at the center-of-mass energy of 1.96 TeV

Description: By way of retaining the gauge invariance of the Standard Model (SM) and giving masses to the W{sup {+-}} and Z{sup 0} bosons and the fermions, the Higgs mechanism predicts the existence of a neutral scalar bosonic particle, whose mass is not exactly known. The Higgs boson is the only experimentally unconfirmed SM particle to date. This thesis documents a search for the Higgs boson in p{bar p} collisions at {radical}s = 1.96 TeV at the Tevatron, using 360 {+-} pb {sup -1} data collected by the R… more
Date: December 1, 2006
Creator: Chuang, Shan-Huei S.
Partner: UNT Libraries Government Documents Department
open access

A search for double-charged Higgs bosons at the Tevatron

Description: We search for the pair production of doubly charged Higgs particles followed by the lepton-flavor violating decay of each Higgs into electron-and-tau and muon-and-tau pairs using 350 pb{sup -1} of data collected by the CDF II experiment at the Fermilab Tevatron. Separate searches investigate cases where three or four final state leptons are detected, and the limits for each exclusive decay mode reflect the combined results of both searches. Assuming the H{sup {+-}{+-}}{sub L} decays exclusively… more
Date: January 1, 2006
Creator: Baraoiant, Sasha
Partner: UNT Libraries Government Documents Department
open access

Exclusive interactions in p anti-p collisions at s**(1/2) = 1.96 TeV

Description: This thesis presents two exclusive production processes in p{bar p} collisions at {radical}s = 1.96 TeV, using the Collider Detector Facility at Fermi National Accelerator Laboratory. An observation of exclusive e{sup +}e{sup -} production through {gamma}{gamma} {yields} e{sup +}e{sup -} is presented, as well as evidence for exclusive production of {gamma}{gamma} through gg {yields} {gamma}{gamma} (via a quark loop). The exclusive e{sup +}e{sup -} production observation is based on 16 candidate… more
Date: May 1, 2006
Creator: Hamilton, Andrew & U., /Alberta
Partner: UNT Libraries Government Documents Department
open access

The Node Monitoring Component of a Scalable Systems Software Environment

Description: This research describes Fountain, a suite of programs used to monitor the resources of a cluster. A cluster is a collection of individual computers that are connected via a high speed communication network. They are traditionally used by users who desire more resources, such as processing power and memory, than any single computer can provide. A common drawback to effectively utilizing such a large-scale system is the management infrastructure, which often does not often scale well as the syste… more
Date: August 9, 2006
Creator: Miller, Samuel James
Partner: UNT Libraries Government Documents Department
open access

Optimization of the signal selection of exclusively reconstructed decays of B0 and B/s mesons at CDF-II

Description: The work presented in this thesis is mainly focused on the application in a {Delta}m{sub s} measurement. Chapter 1 starts with a general theoretical introduction on the unitarity triangle with a focus on the impact of a {Delta}m{sub s} measurement. Chapter 2 then describes the experimental setup, consisting of the Tevatron collider and the CDF II detector, that was used to collect the data. In chapter 3 the concept of parameter estimation using binned and unbinned maximum likelihood fits is lai… more
Date: June 1, 2006
Creator: Doerr, Christian
Partner: UNT Libraries Government Documents Department
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