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Measurement of the W+- + b anti-b cross-section in 695-pb-1 of p anti-p collisions at CDF II.

Description: W{sup {+-}} + b{bar b} events contain the associated production of a W{sup {+-}} boson, a pair of bottom quarks (b{bar b}), and any number of additional partons. This process is of much importance at hadron collider experiments due to its role as a background source in searches for Standard Model Higgs boson and single top-quark production. In this thesis the results are presented for a measurement of the b-jet cross-section in W{sup {+-}} + b{bar b} events containing 1 or 2 jets in 695 pb{sup … more
Date: September 1, 2006
Creator: Soderberg, Mitchell Paul
Partner: UNT Libraries Government Documents Department
open access

Measurement of the B meson Lifetimes with the Collider Detector at Fermilab

Description: The lifetimes of the B{sup -}, B{sup 0} and B{sub s}{sup 0} mesons are measured using partially reconstructed semileptonic decays. Following semileptonic decay processes and their charge conjugates are used for this analysis: B{sup -}/B{sup 0} {yields} {ell}{sup -}{nu}D{sup 0}X; B{sup -}/B{sup 0} {yields} {ell}{sup -}{nu}D*{sup +}X; B{sub s}{sup 0} {yields} {ell}{sup -}{nu}D{sub s}{sup +}x, where {ell}{sup -} denotes either a muon or electron. The data are collected during 2002-2004 by the 8 Ge… more
Date: January 1, 2006
Creator: Uozumi, Satoru
Partner: UNT Libraries Government Documents Department
open access

Images of a Gendered Kingship: Visual Representations of Hatshepsut and Her Influence on Images of Nefertiti

Description: I investigate why gendered images of Hatshepsut influenced androgynous images of Nefertiti in New Kingdom Egypt and how Nefertiti and Akhenaten used their images in the promotion of their monotheistic religion; through a contextual, stylistic and feminist examination of the images. Hatshepsut cultivated images of herself to legitimize her rule in relation to canonical kings before her. Similarly, Nefertiti represented herself as a figure indiscernible from Akhenaten, creating an image of fema… more
Date: August 2006
Creator: Hilliard, Kristina Marie
Partner: UNT Libraries

Style and the Art of Chaim Soutine: Ethnicity, Nationalism and Geography in the Critical Reception and Historiography

Description: This thesis argues that art criticism published during Soutine's lifetime emphasizes ethnicity, nationalism and geography in discussions of the artist's style. These critical discussions have influenced the historiography of Soutine published after his death, resulting in a continued emphasis on style that includes references to ethnicity. Ethnicity, nationalism and geography are identified in the critical reception and historiography by noting references, both specific and implied, to Jewishne… more
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Date: August 2006
Creator: Grance, Heather Anne
Partner: UNT Libraries
open access

N-Acylethanolamine (NAE) Profiles Change During Arabidopsis Thaliana Seed Germination and Seedling Growth

Description: An understanding of the potential roles as lipid mediators of a family of bioactive metabolites called N-acylethanolamines (NAEs) depends on their accurate identification and quantification. The levels of 18C unsaturated NAEs (e.g. NAE18:2, NAE 18:3, etc.) in wild-type seeds (about 2000 ng/g fw) generally decreased by about 80% during germination and post-germinative growth. In addition, results suggest NAE-degradative fatty acid amide hydrolase (FAAH) expression does not play a major role in … more
Date: August 2006
Creator: Wiant, William C.
Partner: UNT Libraries
open access

Well-Being of Gifted Students Following Participation in an Early-College-Entrance Program

Description: The concepts of well-being and life satisfaction are explored in this study of the experiences and psychological traits of highly-gifted students who have been radically accelerated into an early-college-entrance program. The study was conducted after participation in the early-college-entrance program. The primary focus of the study is on personal well-being and life satisfaction including the variables of subjective well-being, efficacy, and the dispositional traits of cheerfulness, seriousne… more
Date: December 2006
Creator: Boazman, Janette Kay
Partner: UNT Libraries
open access

Search for Resonances in the Photoproduction of Proton-Antiproton Pairs

Description: Results are reported on the reaction {gamma}p {yields} p{bar p}p with beam energy in the range 4.8-5.5 GeV. The data were collected at the Thomas Jefferson National Accelerator Facility in CLAS experiment E01-017(G6C). The focus of this study is an understanding of the mechanisms of photoproduction of proton-antiproton pairs, and to search for intermediate resonances, both narrow and broad, which decay to p{bar p}. The total measured cross section in the photon energy range 4.8-5.5 GeV is {sigm… more
Date: June 30, 2006
Creator: Stokes, Burnham
Partner: UNT Libraries Government Documents Department
open access

The Pion Charge Form Factor Through Pion Electroproduction

Description: The goal of Jefferson Lab experiment E01-004 (F?-2) was the measurement of the longitudinal and transverse cross sections via pion electroproduction from hydrogen and deuterium for the purpose of extracting the charged pion form factor using pole dominance. The data were taken at two values of Q2 (1.60 and 2.45 GeV/c)2. In order to attain full coverage in R?, charged pions were detected in parallel kinematics (along the direction of momentum transfer, q), and at ±3 degrees off the direction of… more
Date: April 1, 2006
Creator: Horn, Tanja
Partner: UNT Libraries Government Documents Department
open access

Fast Ignition Experimental and Theoretical Studies

Description: We are becoming dependent on energy more today than we were a century ago, and with increasing world population and booming economies, sooner or later our energy sources will be exhausted. Moreover, our economy and welfare strongly depends on foreign oil and in the shadow of political uncertainties, there is an urgent need for a reliable, safe, and cheap energy source. Thermonuclear fusion, if achieved, is that source of energy which not only will satisfy our demand for today but also for centu… more
Date: October 20, 2006
Creator: Akli, K
Partner: UNT Libraries Government Documents Department
open access

Search For the Rare Decay K(L) ---> pi0 pi0 gamma

Description: This thesis describes a search for the rare decay K{sub L} {yields} {pi}{sup 0}{pi}{sup 0}{gamma} using data from the KTeV experiment, using the topology K{sub L} {yields} {pi}{sup 0}{pi}{sub D}{sup 0}{gamma} (where {pi}{sub D}{sup 0} {yields} {gamma}e{sup +}e{sup -}). Due to Bose statistics and the real nature of the photon, the K{sub L} {yields} {pi}{sup 0}{pi}{sup 0}{gamma} decay can proceed at lowest order only by the Cp conserving direct emission of an E2 photon. The decay vanishes to O(p{… more
Date: August 1, 2006
Creator: Smith, David Edward & U., /Virginia
Partner: UNT Libraries Government Documents Department
open access

Measurement of the Branching fraction ratio B ---> D K / B ---> D pi with the CDF II detector

Description: In this thesis the author has described the first measurement performed at a hadron collider of the branching fraction of the Cabibbo-suppressed mode B{sup +} {yields} {bar D}{sup 0} K{sup +}. The analysis has been performed with 360 pb{sup -1} of data collected by the CDF II detector.
Date: November 1, 2006
Creator: Squillacioti, Paola & /INFN, Pisa /Siena U.
Partner: UNT Libraries Government Documents Department
open access

Inclusive high-p(T) b anti-b cross section measurement at s**(1/2) = 1.96-TeV

Description: The Run II physics program at the Tevatron started in the spring of 2001 with protons and antiprotons colliding at an energy of {radical}s = 1.96 TeV, and is continuing with about 1.2 fb{sup -1} of data currently collected by the CDF and D0 experiments. A measurement of the b-jet cross section as function of jet transverse momentum p{perpendicular} has been performed using 312 pb{sup -1} of D0 data. The results for this measurement were obtained and are presented herein. A neural network algori… more
Date: August 1, 2006
Creator: Galyaev, Eugene N. & U., /Notre Dame
Partner: UNT Libraries Government Documents Department
open access

Implementation of the Immersed Boundary Method in the Weather Research and Forecasting model

Description: Accurate simulations of atmospheric boundary layer flow are vital for predicting dispersion of contaminant releases, particularly in densely populated urban regions where first responders must react within minutes and the consequences of forecast errors are potentially disastrous. Current mesoscale models do not account for urban effects, and conversely urban scale models do not account for mesoscale weather features or atmospheric physics. The ultimate goal of this research is to develop and i… more
Date: December 7, 2006
Creator: Lundquist, K A
Partner: UNT Libraries Government Documents Department
open access

Search for MSSM Higgs decaying to tau pairs in ppbar collision at s**(1/2) = 1.96 TeV at CDF

Description: This thesis presents the search for neutral Minimal Supersymmetric extension of Standard Model (MSSM) Higgs bosons decaying to tau pairs where one of the taus decays leptonically, and the other one hadronically. CDF Run II data with L{sub int} = 310 pb{sup -1} are used. There is no evidence of MSSM Higgs existence, which results in the upper limits on {sigma}(p{bar p} {yields} {phi}) x BR({phi} {yields} {tau}{tau}) in m{sub A} range between 115 and 250 GeV. These limits exclude some area in tan… more
Date: May 1, 2006
Creator: Jang, Dongwook
Partner: UNT Libraries Government Documents Department
open access

High Resolution Studies of the Origins of Polyatomic Ions in Inductively Coupled Plasma-Mass Spectrometry

Description: The inductively coupled plasma (ICP) is an atmospheric pressure ionization source. Traditionally, the plasma is sampled via a sampler cone. A supersonic jet develops behind the sampler, and this region is pumped down to a pressure of approximately one Torr. A skimmer cone is located inside this zone of silence to transmit ions into the mass spectrometer. The position of the sampler and skimmer cones relative to the initial radiation and normal analytical zones of the plasma is key to optimizing… more
Date: August 9, 2006
Creator: Ferguson, Jill Wisnewski
Partner: UNT Libraries Government Documents Department
open access

Designing of Metallic Photonic Structures and Applications

Description: In this thesis our main interest has been to investigate metallic photonic crystal and its applications. We explained how to solve a periodic photonic structure with transfer matrix method and when and how to use modal expansion method. Two different coating methods were introduced, modifying a photonic structure's intrinsic optical properties and rigorous calculation results are presented. Two applications of metallic photonic structures are introduced. For thermal emitter, we showed how to de… more
Date: August 9, 2006
Creator: Kim, Yong-Sung
Partner: UNT Libraries Government Documents Department
open access

Superconducting High Resolution Fast-Neutron Spectrometers

Description: Superconducting high resolution fast-neutron calorimetric spectrometers based on {sup 6}LiF and TiB{sub 2} absorbers have been developed. These novel cryogenic spectrometers measure the temperature rise produced in exothermal (n, {alpha}) reactions with fast neutrons in {sup 6}Li and {sup 10}B-loaded materials with heat capacity C operating at temperatures T close to 0.1 K. Temperature variations on the order of 0.5 mK are measured with a Mo/Cu thin film multilayer operated in the transition re… more
Date: May 25, 2006
Creator: Hau, I D
Partner: UNT Libraries Government Documents Department
open access

The Nature of the Distinctive Microscopic Features in R5(SixGe1-x)4 Magnetic Refrigeration Materials

Description: Magnetic refrigeration is a promising technology that offers a potential for high energy efficiency. The giant magnetocaloric effect of the R{sub 5}(Si{sub x}, Ge{sub 1-x}){sub 4} alloys (where R=rare-earth and O {le} x {le} 1), which was discovered in 1997, make them perfect candidates for magnetic refrigeration applications. In this study the microstructures of Gd{sub 5}(Si{sub x}Ge{sub 1-x}){sub 4} alloys have been characterized using electron microscopy techniques, with the focus being on d… more
Date: May 1, 2006
Creator: Ugurlu, Ozan
Partner: UNT Libraries Government Documents Department
open access

Search for new physics in electron-tau final states in proton - antiproton collisions at 1.96 TeV

Description: During the last decades, particle physicists have studied the tiniest building blocks of matter--the quarks and the leptons--and the forces between them in great detail. From these experiments, a theoretical framework has been built that describes the observed results with high precision. The achievement of this theory, which is referred to as the Standard Model of elementary particle physics, was the elaboration of a unified description of the strong, weak and electromagnetic forces in the fra… more
Date: April 1, 2006
Creator: Noeding, Carsten
Partner: UNT Libraries Government Documents Department
open access

Lifetime difference in the Bs0 system from untagged Bs0 ---> J/psi phi decay at s**(1/2) = 1.96 TeV at D0 detector

Description: In this dissertation, they present a study of the untagged decay of B{sub s}{sup 0} {yields} J/{psi}{phi}, the final state of which is a superposition of the CP-even and CP-odd states. Within the framework of the standard model (SM), to a good approximation, the two CP eigenstates of the (B{sub s}{sup 0}, {bar B}{sub s}{sup 0}) system are equivalent to mass eigenstates. The data collected by the D0 detector between June 2002 to August 2004 (an integrated luminosity of approximately 450 pb{sup -… more
Date: November 1, 2006
Creator: Chandra, Avdhesh & Inst., /Tata
Partner: UNT Libraries Government Documents Department
open access

Magnetic Tools for Lab-on-a-chip Technologies

Description: This study establishes a set of magnetics-based tools that have been integrated with microfluidic systems. The overall impact of the work begins to enable the rapid and efficient manipulation and detection of magnetic entities such as particles, picoliter-sized droplets, or bacterial cells. Details of design, fabrication, and theoretical and experimental assessments are presented. The manipulation strategy has been demonstrated in the format of a particle diverter, whereby micron-sized particle… more
Date: August 5, 2006
Creator: Pekas, Nikola Slobodan
Partner: UNT Libraries Government Documents Department
open access

Measurement of J/psi meson and b-hadron production cross section at sqrt(s) = 1.96 TeV

Description: A new measurement of the inclusive and differential production cross sections of J/{psi} mesons and b-hadrons in proton-antiproton collisions at {radical}s = 1960 GeV is presented. The data correspond to an integrated luminosity of 39.7 pb{sup -1} collected by the CDF Run II detector. The integrated cross section for inclusive J/{psi} production for all transverse momenta from 0 to 20 GeV/c in the rapidity range |y| < 0.6 is found to be 4.08 {+-} 0.02(stat){sub -0.33}{sup +0.36}(syst) {mu}b.… more
Date: March 1, 2006
Creator: Yamashita, Tomohiro & U., /Okayama
Partner: UNT Libraries Government Documents Department
open access

Analysis of Bs flavor oscillations at CDF

Description: The search for and study of flavor oscillations in the neutral B{sub s}B{sub s} meson system is an experimentally challenging task. It constitutes a flagship analysis of the Tevatron physics program. In this dissertation, they develop an analysis of the time-dependent B{sub s} flavor oscillations using data collected with the CDF detector. The data samples are formed of both fully and partially reconstructed B meson decays: B{sub s} {yields} D{sub s}{pi}({pi}{pi}) and B{sub s} {yields} D{sub s}… more
Date: September 1, 2006
Creator: Leonardo, Nuno T.
Partner: UNT Libraries Government Documents Department
open access

Measuring the branching ratio of the rare decay pi0 --> e+ e-

Description: A precise branching ratio measurement of the rare decay {pi}{sup 0} {yields} e{sup +}e{sup -} has been made. The measurement was made with the rare kaon decay experiment KTeV at Fermilab where the source of {pi}{sup 0}s was K{sub L} {yields} {pi}{sup 0}{pi}{sup 0}{pi}{sup 0} decaying in flight. A total of 794 fully reconstructed K{sub L} {yields} 3{pi}{sup 0} events consistent with two of the intermediate {pi}{sup 0}s decaying into {gamma}{gamma} and one into e{sup +}e{sup -} were collected. An… more
Date: February 1, 2006
Creator: Niclasen, Rune
Partner: UNT Libraries Government Documents Department
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