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Measurement of the ttbar production cross section in the MET+jets channel at CDF

Description: This thesis is focused on an inclusive search of the t{bar t} {yields} E{sub T} + jets decay channel by means of neural network tools in proton antiproton collisions at {radical}s = 1.96 TeV recorded by the Collider Detector at Fermilab (CDF). At the Tevatron p{bar p} collider top quarks are mainly produced in pairs through quark-antiquark annihilation and gluon-gluon fusion processes; in the Standard Model description, the top quark then decays to a W boson and a b quark almost 100% of the tim… more
Date: March 1, 2008
Creator: Compostella, Gabriele & /INFN, Trento
Partner: UNT Libraries Government Documents Department
open access

Study on the top quark pair production mechanism in 1.96 TeV proton-antiproton collisions

Description: The study of the top quark pair production mechanism in proton-antiproton collisions at a center-of-mass energy of 1.96 TeV is described. The main subjects are the measurements of the top quark pair production cross section, the top quark mass and a search for a new particle decaying to the top quark pair. The analyses are based on 1.9 fb{sup -1} of data collected by the Collider Detector at Fermilab (CDF) Run II experiment between March 2002 and May 2007, using the lepton+jets events. The meas… more
Date: March 1, 2008
Creator: Naganoma, Junji & U., /Waseda
Partner: UNT Libraries Government Documents Department
open access

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

Neutrino induced events in the MINOS detectors

Description: The MINOS experiment is designed to study neutrino oscillations. It uses an accelerator generated beam of neutrinos and two detectors, the smaller at a distance of 1km and the larger at 735 km. By comparing the spectrum and flavour composition of the beam at the two detectors precise determinations of the oscillation parameters are possible. This thesis concentrates on the analysis of data from the larger Far Detector. By studying the spectrum of neutral current events it is possible to look fo… more
Date: March 1, 2008
Creator: Litchfield, Reuben Phillip
Partner: UNT Libraries Government Documents Department
open access

Novel Regenerated Solvent Extraction Processes for the Recovery of Carboxylic Acids or Ammonia from Aqueous Solutions Part II. Recovery of Ammonia from Sour Waters

Description: Two novel regenerated solvent extraction processes are examined. The first process has the potential to reduce the energy costs inherent in the recovery of low-volatility carboxylic acids from dilute aqueous solutions. The second process has the potential for reducing the energy costs required for separate recovery of ammonia and acid gases (e.g. CO{sub 2} and H{sub 2}S) from industrial sour waters. The recovery of carboxylic acids from dilute aqueous solution can be achieved by extraction with… more
Date: March 1, 1990
Creator: Poole, L. J. & King, C. J.
Partner: UNT Libraries Government Documents Department
open access

Search for WW and WZ production in lepton, neutrino plus jets final states at CDF Run II and Silicon module production and detector control system for the ATLAS SemiConductor Tracker

Description: In the first part of this work, we present a search for WW and WZ production in charged lepton, neutrino plus jets final states produced in p{bar p} collisions with {radical}s = 1.96 TeV at the Fermilab Tevatron, using 1.2 fb{sup -1} of data accumulated with the CDF II detector. This channel is yet to be observed in hadron colliders due to the large singleWplus jets background. However, this decay mode has a much larger branching fraction than the cleaner fully leptonic mode making it more sens… more
Date: March 1, 2008
Creator: Sfyrla, Anna & U., /Geneva
Partner: UNT Libraries Government Documents Department
open access

Novel Regenerated Solvent Extraction Processes for the Recovery of Carboxylic Acids or Ammonia from Aqueous Solutions Part I. Regeneration of Amine-Carboxylic Acid Extracts

Description: Two novel regenerated solvent extraction processes are examined. The first process has the potential to reduce the energy costs inherent in the recovery of low-volatility carboxylic acids from dilute aqueous solutions. The second process has the potential for reducing the energy costs required for separate recovery of ammonia and acid gases (e.g. CO{sub 2} and H{sub 2}S) from industrial sour waters. The recovery of carboxylic acids from dilute aqueous solution can be achieved by extraction with… more
Date: March 1, 1990
Creator: Poole, L. J. & King, C. J.
Partner: UNT Libraries Government Documents Department
open access

CHARGE-EXCHANGE SCATTERING OF NEGATIVE PIONS BY HYDROGEN AT 230,260, 290, 317 AND 371 MeV

Description: The differential cross section for charge-exchange scattering of negative pions by hydrogen has been observed at 230, 260, 290, 317, and 371 Mev. The reaction was observed by detecting one gamma ray from the {pi}{sup 0} decay with a scintillation-counter telescope.
Date: March 18, 1960
Creator: Caris, John C
Partner: UNT Libraries Government Documents Department
open access

Top quark mass measurement

Description: No Description Available.
Date: March 1, 2008
Creator: Maki, Tuula & Tech., /Helsinki Inst. of Phys. /Helsinki U. of
Partner: UNT Libraries Government Documents Department
open access

Measurement of the Ratio of Branching Fractions Br(Bs -> Ds- pi+)/Br(B -> D- pi+) at CDF-II

Description: The measurement of B{sub s}{sup 0} mixing is one of the flagship analyses for the Run II B physics program. The sensitivity of the measurement to the frequency of B{sub s}{sup 0} oscillations strongly depends on the number of reconstructed B{sub s}{sup 0} mesons. They present the measurement of the ratio of branching fractions Br(B{sub s}{sup 0} {yields} D{sub s}{sup -}{pi}{sup +})/Br(B{sup 0} {yields} D{sup -}{pi}{sup +}), which directly influences the number of B{sub s}{sup 0} events availabl… more
Date: March 1, 2004
Creator: Furic, Ivan Kresimir
Partner: UNT Libraries Government Documents Department
open access

Fluidization characteristics of power-plant fly ashes and fly ash-charcoal mixtures.

Description: As a part of the continuing research on aluminum recovery from fly ash by HiChlor process, a plexiglass fluidization column system was constructed for measurement of fluidization parameters for power-plant fly ashes and fly ash-charcoal mixtures. Several bituminous and subbituminous coal fly ashes were tested and large differences in fluidization characteristics were observed. Fly ashes which were mechanically collected fluidized uniformly at low gas flow rates. Most fly ashes which were electr… more
Date: March 1, 1980
Creator: Nguyen, C. T.
Partner: UNT Libraries Government Documents Department
open access

A photoemission study of the diamond and the single crystal C{sub 60}

Description: This report studied the elctronic structure of diamond (100) and diamond/metal interface and C{sub 60}, using angle-resolved and core level photoemission. The C(100)-(2X1) surface electronic structure was studied using both core level and angle resolved valence band photoemission spectroscopy. The surface component of the C 1s core level spectrum agrees with theoretical existence of only symmetrical dimers. In the case of metal/diamond interfaces, core level and valence photoelectron spectrosco… more
Date: March 1, 1994
Creator: Wu, Jin
Partner: UNT Libraries Government Documents Department
open access

Models to evaluate magnicon architectures and designs suitable for high-perveance beams

Description: The magnicon, a new high-power, radio frequency (rf) deflection- modulated amplifier, was recently developed at the Institute for Nuclear Physics in Novosibirsk, Russia. The first magnicon achieved a peak output power of 2.6 MW for 50-{mu}s pulses at a frequency of 915 MHz with a dc-to-rf conversion efficiency of 73%. The conversion efficiency achieved by the original magnicon represents a significant improvement over state-of-the-art conventional velocity- and density-modulated devices. Theref… more
Date: March 1, 1994
Creator: Rees, D. E.
Partner: UNT Libraries Government Documents Department
open access

Velocity measurements of low Reynolds number tube flow using fiber-optic technology

Description: In 1988 Nielsen started work to measure the spatial variability of the mass flux vector being transported in a porous medium. To measure the spatial variability of the mass flux vector, the spatial variability of its components(velocity, concentration) must be measured. Nielsen was successful in measuring the pore level concentration at many different pores and in verifying the assumption that a nonuniform concentration field exists within the mixing zone between two miscible fluids. However, N… more
Date: March 1, 1993
Creator: Bianchi, J. C.
Partner: UNT Libraries Government Documents Department
open access

Quaternary liquid/liquid equilibria of sodium sulfate, sodium sulfite and water with two solvents: Acetone and 2-propanol

Description: Aqueous solutions of sodium sulfate and sodium sulfite are produced from sodium carbonate in flue-gas scrubbers; recovery of these salts often requires multi-effect evaporators; however, a new energy-efficient unit operation called extractive crystallization has been shown to have reduced energy costs. In this process, an organic solvent is added to the aqueous salt solution to precipitate salt. Acetone is a suitable solvent for this process, better than 2-propanol. Liquid/liquid/solid equilibr… more
Date: March 1, 1994
Creator: Schiozer, A. L.
Partner: UNT Libraries Government Documents Department
open access

Chemisorption and catalytic reactivity of cobalt and sulfur monolayers on ordered molybdenum surfaces

Description: Complex Co/Mo sulfide catalysts are modelled by the chemisorption of layers on Mo single crystal surfaces. Growth and structure of overlayers on flat, stepped and kinked surfaces were investigated. Growth of Co overlayers on clean and S covered Mo surfaces was studied using AES and CO chemisorption; results reveal that Co grows as a flat monolayer on clean Mo surfaces. Co multilayers then form 3-D islands. When Co is deposited on S covered surfaces, the S overlayer migrates to the top; this top… more
Date: March 1, 1992
Creator: Knight, C. C.
Partner: UNT Libraries Government Documents Department
open access

Signal and noise analysis of a-Si:H radiation detector-amplifier system

Description: Hydrogenated amorphous silicon (a-Si:H) has potential advantages in making radiation detectors for many applications because of its deposition capability on a large-area substrate and its high radiation resistance. Position-sensitive radiation detectors can be made out of a 1d strip or a 2-d pixel array of a Si:H pin diodes. In addition, signal processing electronics can be made by thin-film transistors on the same substrate. The calculated radiation signal, based on a simple charge collection … more
Date: March 1, 1992
Creator: Cho, Gyuseong
Partner: UNT Libraries Government Documents Department
open access

Energy development and CO{sub 2} emissions in China

Description: The objective of this research is to provide a better understanding of future Chinese energy development and CO{sub 2} emissions from burning fossil fuels. This study examines the current Chinese energy system, estimates CO{sub 2} emissions from burning fossil fuels and projects future energy use and resulting CO{sub 2} emissions up to the year of 2050. Based on the results of the study, development strategies are proposed and policy implications are explored. This study first develops a Base s… more
Date: March 1, 1993
Creator: Xiaolin Xi
Partner: UNT Libraries Government Documents Department
open access

Design and test of a low jitter metal to metal contact solid dielectric switch

Description: A low jitter metal to metal contact solid dielectric switch was designed and tested. A metal to metal contact solid dielectric switch with a jitter of less than 25 ns is required for the 150 kJ experiment. Since this is one fourth the 100 ns jitter reported using exploding bridge foil (EBF) triggers, experiments to optimize this trigger were performed. A jitter of 25 ns was achieved using the EBF trigger and it was also achieved using a new type of trigger called the magnetic push trigger. This… more
Date: March 1, 1993
Creator: Domning, E. E.
Partner: UNT Libraries Government Documents Department
open access

Implantation of carbon in GaAs

Description: Carbon implanted into GaAs and thermally annealed typically exhibits very low (<3%) electrical activity. It has been demonstrated that the electrical activity of C can be significantly enhanced by co-implantation with Ga. Improved activation may result from either additional damage of the crystal lattice or from stoichiometric changes, forcing the C atoms onto As sites. To determine the relative importance of each of these effects, I have undertaken a systematic study of carbon activation in Ga… more
Date: March 1, 1992
Creator: Moll, A. J.
Partner: UNT Libraries Government Documents Department
open access

Search for first-generation leptoquarks in the jets and missing transverse energy topology in proton-antiproton collisions at center-of-mass energy 1.96 TeV

Description: The authors performed a search for the pair production of first-generation leptoquarks using 191 pb{sup -1} of proton-antiproton collision data recorded by the CDF experiment during Run II of the Tevatron. The leptoquarks are sought via their decay into a neutrino and quark, which yields missing transverse energy and several high-E{sub T} jets. Several control regions were studied to check the background estimation from Standard Model sources, with good agreement observed in data. In the leptoq… more
Date: March 1, 2004
Creator: Tsybychev, Dmitri
Partner: UNT Libraries Government Documents Department
open access

Mass spectrum analysis of K- pi+ from the semileptonic decay D+ --> K- pi+ mu+ nu

Description: The Higgs mechanism preserves the gauge symmetries of the Standard Model while giving masses to the W, Z bosons. Supersymmetry, which protects the Higgs boson mass scale from quantum corrections, predicts at least 5 Higgs bosons, none of which has been directly observed. This thesis presents a search for neutral Higgs bosons, produced in association with bottom quarks. The production rate is greatly enhanced at large values of the Supersymmetric parameter tan {beta}. High-energy p{bar p} collis… more
Date: March 1, 2004
Creator: Massafferri Rodrigues, Andre & /Rio de Janeiro, CBPF
Partner: UNT Libraries Government Documents Department
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