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Electron microscopy of hydrocarbon production in parthenium argentatum (guayule)

Description: The electron microscope was used to study the biological processes involved in hydrocarbon production. The little desert shrub Guayule (Parthenium argentatum) was selected for study. This shrub can produce hydrocarbons (rubber) in concentrations up to 1/4 of its dry weight. It grows on semi-arid land and has been extensively studied. The potential of Guayule is described in detail. Results of an investigation into the morphology of Guayule at the electron microscope level are given. Experiments… more
Date: November 1, 1977
Creator: Bauer, T.E.
Partner: UNT Libraries Government Documents Department
open access

Investigation of high energy runaway electron confinement in the Oak Ridge tokamak

Description: High energy runaway electrons in the Oak Ridge tokamak ORMAK have been investigated through measurement of the bremsstrahlung produced when these electrons leave the discharge and strike the limiting aperture of the torus. The experimental results have been interpreted in terms of a classical single-particle model appropriate for collisionless particles in a tokamak, and it has been found that most of the confinement properties of high energy runaways in ORMAK can be understood on this basis. A… more
Date: November 1, 1977
Creator: Zweben, S. J.
Partner: UNT Libraries Government Documents Department
open access

A measurement of the top quark's charge

Description: The top quark was discovered in 1995 at the Fermilab National Accelerator Laboratory (Fermilab). One way to confirm if the observed top quark is really the top quark posited in the Standard Model (SM) is to measure its electric charge. In the Standard Model the top quark is the isospin partner of the bottom quark and is expected to have a charge of +2/3. However, an alternative 'exotic' model has been proposed with a fourth generation exotic quark that has the same characteristics, such as mass… more
Date: November 1, 2007
Creator: Unalan, Zeynep Gunay
Partner: UNT Libraries Government Documents Department
open access

A Search For The Z -> b anti-b Process at The D-Zero Experiment

Description: In 2001, the D0 experiment entered a new era. Run II of the Tevatron at the Fermi National Accelerator Laboratory began, and the collider became the highest energy particle accelerator in the world. Accordingly, the D0 detector had already undergone a series of upgrades in order to fully exploit the physics now within reach. These included improvements to the tracking, calorimetry, muon detection and triggering capabilities. In the Standard Model, the Higgs boson is the last piece of the puzzle… more
Date: November 1, 2006
Creator: Jenkins, Amber Helen
Partner: UNT Libraries Government Documents Department
open access

Jet Energy Scale Studies and the Search for the Standard Model Higgs Boson in the Channel ZH -> nu anti-nu b anti-b at D�

Description: The D0 experiment is based at the Tevatron, which is currently the world's highest-energy accelerator. The detector comprises three major subsystems: the tracking system, the calorimeter and the muon detector. Jets, seen in the calorimeter, are the most common product of the proton-proton interactions at 2TeV. This thesis is divided into two parts. The first part focuses on jets and describes the derivation of a jet energy scale using p{bar p} {yields} (Z + jets) events as a cross-check of the … more
Date: November 1, 2006
Creator: Lobo, Lydia Mary Isis
Partner: UNT Libraries Government Documents Department
open access

The Differential cross section distribution of Drell-Yan dielectron pairs in the z boson mass region

Description: We report on a measurement of the rapidity distribution, d{sigma}/dy, for Z=Drell-Yan {yields} ee events produced in p{bar p} collisions at {radical}s = 1.96 TeV. The data sample consists of 2.13 fb{sup -1} corresponding to about 160,000 Z/Drell-Yan {yields} ee candidates in the Z boson mass region collected by the Collider Detector at Fermilab. The d{sigma}/dy distribution, which is measured over the full kinematic range for e{sup +}e{sup -} pairs in the invariant mass range 66 < M{sub ee} … more
Date: November 1, 2008
Creator: Han, Jiyeon
Partner: UNT Libraries Government Documents Department
open access

A Search for Direct CP Violation in Two-Body Cabibbo-Suppressed Decays of Neutral Charmed Mesons

Description: Presented are the results of a search for direct CP violation in Cabibbo-suppressed decays of D{sup 0} to two charged daughters. The analysis described was performed on {approx}230 fb{sup -1} of the BABAR data sample, recorded at the Stanford Linear Accelerator Center and using the PEP-II electron storage rings. We measure CP asymmetries for decay to the KK and {pi}{pi} final states, as well as for the branching ratio, and develop a new technique for tagging-efficiency correction using the Cabi… more
Date: November 12, 2007
Creator: Flacco, Christian Julienne & /UC, Santa Cruz
Partner: UNT Libraries Government Documents Department
open access

First observation of the Bs->K+K- decay mode, and measurement of the B0 and Bs mesons decay-rates into two-body charmless final states at CDF

Description: The authors searched for decays of the type B{sub (s)}{sup 0} {yields} h{sup +}h{prime}{sup -} (where h, h{prime} = K or {pi}) in a sample corresponding to 180 pb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV, collected by the upgraded Collider Detector at the Fermilab Tevatron. A total signal of approximately 900 events was reconstructed, and the relative branching fractions ({Beta}) of each decay mode were determined with a likelihood fit.
Date: November 1, 2006
Creator: Tonelli, Diego & /Pisa, Scuola Normale Superiore
Partner: UNT Libraries Government Documents Department
open access

First measurement of top quark pair production cross-section in muon plus hadronic tau final states

Description: This dissertation presents the first measurement of top quark pair production cross-section in events containing a muon and a tau lepton. The measurement was done with 1 fb{sup -1} of data collected during April 2002 through February 2006 using the D0 detector at the Tevatron proton-antiproton collider, located at Fermi National Accelerator Laboratory (Fermilab), Batavia, Illinois. Events containing one isolated muon, one tau which decays hadronically, missing transverse energy, and two or more… more
Date: November 1, 2007
Creator: Sumowidagdo, Suharyo
Partner: UNT Libraries Government Documents Department
open access

Measurement of z boson transverse momentum in proton - anti-proton collisions at s**(1/2) = 1.96 TeV

Description: This dissertation describes a measurement of the shape of the boson transverse momentum distribution in p{bar p} {yields} Z/{gamma}* {yields} e{sup +}e{sup -} + X events at a center-of-mass energy of 1.96 TeV. The measurement is made for events with electron-positron mass between 70 < M{sub ee} < 110 GeV/c{sup 2} and uses 976 pb{sup -1} of data collected at the Fermilab Tevatron collider with the D0 detector. The shape is measured both for the inclusive sample and for the subset of events… more
Date: November 1, 2007
Creator: Wang, Lei
Partner: UNT Libraries Government Documents Department
open access

Single-Mode VISAR

Description: High energy-density physics (HEDP) experiments examine the properties of materials under extreme conditions. These experiments rely on the measurement of one or two velocities. These velocities are used to obtain Hugoniot relationships and thermodynamic equations of state. This methodology is referred to as 'velocimetry' and an instrument used to measure the shock wave is called a 'velocimeter' or a '(velocity) diagnostic'. The two most-widely used existing velocity diagnostics are; photonic Do… more
Date: November 16, 2007
Creator: Krauter, K
Partner: UNT Libraries Government Documents Department
open access

Measurement of the tt, WW and Z -> tautau Production Cross Sections in p anti-p collisions at s**(1/2) = 1.96 TeV

Description: In this thesis we present a new technique to analyze events containing two highly energetic leptons, as a probe of the Standard Model. The philosophy is to consider the data in a more global way, as opposed to the more traditional process dependent approach of extracting a given signal over the expected backgrounds by using various kinematical requirements. We use our global technique to simultaneously measure the cross sections of the main Standard Model processes; the t{bar t}, WW and Z {yiel… more
Date: November 1, 2006
Creator: Carron Montero, Sebastian Fernando & U., /Duke
Partner: UNT Libraries Government Documents Department
open access

Search for new heavy charged gauge bosons

Description: Additional gauge bosons are introduced in many theoretical extensions to the Standard Model. A search for a new heavy charged gauge boson W{prime} decaying into an electron and a neutrino is presented. The data used in this analysis was taken with the D0 detector at the Fermilab proton-antiproton collider at a center-of-mass energy of 1.96 TeV and corresponds to an integrated luminosity of about 1 fb{sup -1}. Since no significant excess is observed in the data, an upper limit is set on the prod… more
Date: November 1, 2007
Creator: Magass, Carsten Martin & U., /RWTH Aachen
Partner: UNT Libraries Government Documents Department
open access

Measurement of the lifetime difference and cp-violating phase in B_s -> J/psi phi decays

Description: Over the past decades the current theoretical description, the Standard Model of elementary particle physics, was solidified by many measurements as the basic theory describing fundamental particles and their interactions. It is extremely successful in explaining the high-precision data collected by experiments so far. The Standard Model includes several intrinsic parameters which have to be measured in experiments. Independent analyses of different physical processes can constrain those parame… more
Date: November 1, 2007
Creator: Milnik, Michael
Partner: UNT Libraries Government Documents Department
open access

Search for the Higgs Boson and Technicolor Particles in p anti-p Colisions at sqrt(s) = 1.8 TeV

Description: In the Standard Model (SM) of the elementary particles, the interactions among the known fundamental fermions (leptons and quarks) are mediated through gauge bosons which obey the symmetry: SU(3) {circle_times} SU(2) {circle_times} U(1). More precisely, the electroweak interaction [4-6] is described by a gauge symmetry SU(2) {circle_times} U(1) which is broken spontaneously. The electroweak symmetry breaking is implemented by the introduction of a complex scalar Higgs field which has a non-zero… more
Date: November 1, 1999
Creator: Cortabitarte, Rocio Vilar & /Cantabria U., Santander
Partner: UNT Libraries Government Documents Department
open access

Measurement of the B+-_c Meson Lifetime Using B+-_c -> J/psi + l+- + X Decays

Description: This thesis describes a measurement of the average proper decay time of the B{sub c}{sup {+-}} mesons, the ground state of bottom and charm quark bound states. The lifetime measurement is carried out in the decay modes B{sub c}{sup {+-}} {yields} J/{psi} + e{sup {+-}} + X and B{sub c}{sup {+-}} {yields} J/{psi} + {mu}{sup {+-}} + X, where the J/{psi} decays as J/{psi} {yields} {mu}{sup +}{mu}{sup -} and the X are unmeasured particles such as {nu}{sub e} or {nu}{sub {mu}}. The data are collect b… more
Date: November 1, 2008
Creator: Hartz, Mark Patrick & U., /Pittsburgh
Partner: UNT Libraries Government Documents Department
open access

Search for electroweak single top-quark production with the CDF II experiment

Description: Understanding the world -- This aim drives humankind since the beginning of conscious thinking. Especially the nature of matter has been of major interest. Nowadays, we have a complex image of the constitution of matter. Atoms consist of electrons and nucleons. But even nucleons are not elementary. Their basic constituents are called quarks. Physicists developed a model describing the elementary components of matter as well as the forces between them: the standard model of elementary particle p… more
Date: November 1, 2007
Creator: Richter, Svenja
Partner: UNT Libraries Government Documents Department
open access

First Observation of An Excited Charm Baryon Decaying to Omega Charm Baryon at the BaBar Experiment

Description: We have carried out a search for a charmed baryon {Omega}{sup *}{sub c} decaying to {Omega}{sup 0}{sub c} and a {gamma} where {Omega}{sub c} candidates are reconstructed using decay modes {Omega}{sup -}{pi}{sup +}(c1), {Omega}{sup -}{pi}{sup +}{pi}{sup 0}(c2), {Omega}{sup -}{pi}{sup +}{pi}{sup -}{pi}{sup +}(c3) and {Xi}{sup -}K{sup -}{pi}{sup +}{pi}{sup +}(c4). This search is performed by analyzing integrated luminosity of 230.7 fb{sup -1} data collected by the BABAR detector at the Stanford Li… more
Date: November 26, 2007
Creator: Bula, Rahmi & /SUNY, Albany
Partner: UNT Libraries Government Documents Department
open access

Trace Elemental Analysis of Ashes in the Combustion of the Binder Enhanced d-RDF by Inductively Coupled Plasma Atomic Emission Spectroscopy

Description: Incineration is an attractive solution to the problems of disposing of municipal solid wastes and supplying energy. Because up to 25 percent of the waste in refuse-derived-fuel systems is ash, the physical and chemical characteristics of ash become more and more important for its potential impacts and methods suitable for their disposal. Trace elements concentration in ash is of great interest because of its relationship to regulatory criteria under the Resource Conservation and Recovery Act (R… more
Date: November 1988
Creator: Tai, Chia-Hui
Partner: UNT Libraries
open access

Single crystalline elastic constants of the MgCu/sub 2/-MgZn/sub 2/ system

Description: The adiabatic single crystalline elastic constants of six Mg(Cu, Zn)/sub 2/ cubic Laves phases have been determined by the ultrasonic pulse-echo technique over the compositional range 10 to 50 mol % MgZn/sub 2/ and over the temperature range 4.2 to 300/sup 0/K. In addition the elastic constants of the hexagonal MgZn/sub 2/ Laves phase were measured as a function of temperature. A minimum exists in the compositional dependence of the cubic Mg(Cu, Zn)/sub 2/ phase at 20 mol % MgZn/sub 2/ for all … more
Date: November 1968
Creator: Shannette, Gary Wayne
Partner: UNT Libraries Government Documents Department
open access

Transient and temperature-dependent phenomena in Ge:Be and Ge:Zn far infrared photoconductors

Description: An experimental study of the transient and temperature-dependent behavior of Ge:Be and Ge:Zn photoconductors has been performed under the low background photon flux conditions (p dot approx. = 10/sup 8/ photons/second) typical of astronomy and astrophysics applications. The responsivity of Ge:Be and Ge:Zn detectors is strongly temperature-dependent in closely compensated material, and the effect of compensation on free carrier lifetime in Ge:Be has been measured using the photo-Hall effect tech… more
Date: November 1985
Creator: Haegel, Nancy Marie
Partner: UNT Libraries Government Documents Department
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