84 Matching Results

Search Results

Results: 1 - 24 next
open access

Measurement of sigma(ppbar->Z) Br(Z->tau+tau-) and search for Higgs bosons decaying to tau+tau- at s**(1/2) = 1.96 TeV

Description: The resonant production of tau-lepton pairs is as interesting for the study of Standard Model (SM) physics as the production of lighter leptons pairs. For new phenomena, such as Higgs boson production or in case new particles beyond the SM would arise, the detection of (resonant) pairs of tau leptons becomes much more interesting. This is due to the fact that tau leptons are much heavier than the other leptons, which increases the chance that these new phenomena would be observed first in this … more
Date: January 1, 2008
Creator: Galea, Cristina Florina & U., /Nijmegen
Partner: UNT Libraries Government Documents Department
open access

A measurement of hadron production cross sections for the simulation of accelerator neutrino beams and a search for muon-neutrino to electron-neutrino oscillations in the delta m**2 about equals 1-eV**2 region

Description: A measurement of hadron production cross-sections for the simulation of accelerator neutrino beams and a search for muon neutrino to electron neutrino oscillations in the {Delta}m{sup 2} {approx} 1 eV{sup 2} region. This dissertation presents measurements from two different high energy physics experiments with a very strong connection: the Hadron Production (HARP) experiment located at CERN in Geneva, Switzerland, and the Mini Booster Neutrino Experiment (Mini-BooNE) located at Fermilab in Bata… more
Date: January 1, 2008
Creator: Schmitz, David W.
Partner: UNT Libraries Government Documents Department
open access

A Study of Charged Current Single Charged Pion Productions on Carbon in a Few-GeV Neutrino Beam

Description: Understanding single charged pion production via neutrino-nucleus charged current interaction in the neutrino energy region of a few GeV is essential for future neutrino oscillation experiments since this process is a dominant background for {nu}{sub {mu}} {yields} {nu}{sub x} oscillation measurements. There are two contributions to this process: single pion production via baryonic resonance ({nu}{sub {mu}}N {yields} {mu}{sup -} N{pi}{sup +}) and coherent pion production interacting with the en… more
Date: January 1, 2009
Creator: Hiraide, Katsuki & U., /Kyoto
Partner: UNT Libraries Government Documents Department
open access

Search for the Higgs boson produced in association with a W boson at CDF Run II

Description: We present a search for standard model Higgs boson production in association with a W boson in proton-antiproton collisions (p{bar p} {yields} W{sup {+-}}H {yields} {ell}{nu}b{bar b}) at a center of mass energy of 1.96 TeV. WH candidate events have a signature of a single lepton (E{sup {+-}}/{mu}{sup {+-}}), missing transverse energy, and two jets. The search looks for candidate events in approximately 2.7 fb{sup -1} of data recorded with the CDF II detector. The high-p{sub T} lepton (e,{mu}) i… more
Date: January 1, 2009
Creator: Slaunwhite, Jason Michael
Partner: UNT Libraries Government Documents Department
open access

MEASUREMENT OF Z + GAMMA PRODUCTION AND SEARCH FOR ANOMALOUS TRIPLE GAUGE COUPLINGS IN PROTON-ANTIPROTON COLLISIONS AT s**(1/2) = 1.96 TEV

Description: The author presents a measurement of p{bar p} {yields} Z{gamma} + X {yields} e{sup +}e{sup -}{gamma} + X production using proton-antiproton collisions data collected at the Collider Detector at Fermilab at a center of mass energy of 1.96 TeV. Z{gamma} production provides a direct test of the triple neutral gauge couplings. A measurement of Z{gamma} production cross section and search for anomalous ZZ{gamma} and Z{gamma}{gamma} couplings are presented. The data presented are from 1.1 fb{sup -1} … more
Date: January 1, 2008
Creator: Deng, Jianrong & U., /Duke
Partner: UNT Libraries Government Documents Department
open access

Measurement of the Diphoton Differential Cross Section in p anti-p Collisions at s**(1/2) = 1.96-TeV

Description: The diphoton differential cross-section as a function of mass up to 300 GeV/c{sup 2}, q{sub T} up to 100 GeV/c, and opening angle over a range of 0 to {pi} radians is measured. The measurement is performed using 1046.19 pb{sup -1} of data collected at Fermi National Accelerator Laboratory using the D0 detector. This analysis considers all direct diphoton states but attempts to suppress contributions due to fragmentation.
Date: January 1, 2007
Creator: Dyer, Joshua Marc
Partner: UNT Libraries Government Documents Department
open access

A Study of Factorization and a Measurement of CP Violation

Description: We report on a study of the decay {bar B}{sup 0} {yields} D*{sup +} {omega}{pi}{sup -} with the BABAR detector at the PEP-II B-factory at the Stanford Linear Accelerator Center. Based on a sample of 232 million B{sup 0}{bar B}{sup 0} decays collected between 1999 and 2004, we measure the branching fraction {Beta}({bar B}{sup 0} {yields} D*{sup +} {omega}{pi}{sup -}) = (2.88 {+-} 0.21(stat.) {+-} 0.31(syst.)) x 10{sup -3}. We study the invariant mass spectrum of the {omega}{pi}{sup -} system in … more
Date: January 16, 2008
Creator: Dahmes, Bryan
Partner: UNT Libraries Government Documents Department
open access

An improved Neutrino Oscillations Analysis of the MiniBooNE Data

Description: We calculate the exclusion region in the parameter space of {nu}{sub {mu}} {yields} {nu}{sub e} oscillations of the LSND type using a combined fit to the reconstructed energy distributions of neutrino candidate samples from the MiniBooNE data obtained with two different particle identification methods. The two {nu}{sub e} candidate samples are included together with a high statistics sample of {nu}{sub {mu}} events in the definition of a {chi}{sup 2} statistic which includes the correlations be… more
Date: January 1, 2008
Creator: Aguilar-Arevalo, Alexis Armando
Partner: UNT Libraries Government Documents Department
open access

A Simultaneous Measurement of the Branching Fractions of Ten B to Double Charm Decays

Description: This dissertation presents a simultaneous measurement of the branching fractions of ten B {yields} D{sup (*)}{bar D}{sup (*)} decays. The measurements are derived from a sample of 2.32 x 10{sup 8} B{bar B} pairs collected by the BABAR detector at the PEP-II B Factory located at Stanford Linear Accelerator Center. The branching fractions (x 10{sup -4}) are: -0.10 {+-} 0.44 {+-} 0.15 (<0.59) for B{sup 0} {yields} D{sup 0}{bar D}{sup 0}; 1.01 {+-} 1.07 {+-} 0.35 (<2.92) for B{sup 0} {yields}… more
Date: January 16, 2008
Creator: Lae, Chung Khim
Partner: UNT Libraries Government Documents Department
open access

Electrochemical arsenic remediation for rural Bangladesh

Description: Arsenic in drinking water is a major public health problem threatening the lives of over 140 million people worldwide. In Bangladesh alone, up to 57 million people drink arsenic-laden water from shallow wells. ElectroChemical Arsenic Remediation(ECAR) overcomes many of the obstacles that plague current technologies and can be used affordably and on a small-scale, allowing for rapid dissemination into Bangladesh to address this arsenic crisis. In this work, ECAR was shown to effectively reduce 5… more
Date: January 1, 2009
Creator: Addy, Susan Amrose
Partner: UNT Libraries Government Documents Department
open access

Search for Rare Quark-Annihilation Decays, Charged B Mesons Decaying to Charged D(S) Mesons And Phi Mesons

Description: The authors report on a search for the decay B{sup {+-}} {yields} D{sub s}{sup (*){+-}} {phi} using 212.2 fb{sup -1} of data collected with the BABAR detector at the PEP-II B Factory at the Stanford Linear Accelerator Center between 1999 and 2004. This sample of 234 x 10{sup 6} e{sup +}e{sup -} {yields} {Upsilon}(4S) {yields} B{bar B} events yields no significant signal. They report the Bayesian upper limits {Beta}(B{sup {+-}} {yields} D{sub s}{sup {+-}} {phi}) x {Beta}(D{sub s}{sup {+-}} {yiel… more
Date: January 16, 2008
Creator: Cunha, J.Adam M.
Partner: UNT Libraries Government Documents Department
open access

Parametric Model for Astrophysical Proton-Proton Interactions and Applications

Description: Observations of gamma-rays have been made from celestial sources such as active galaxies, gamma-ray bursts and supernova remnants as well as the Galactic ridge. The study of gamma rays can provide information about production mechanisms and cosmic-ray acceleration. In the high-energy regime, one of the dominant mechanisms for gamma-ray production is the decay of neutral pions produced in interactions of ultra-relativistic cosmic-ray nuclei and interstellar matter. Presented here is a parametric… more
Date: January 29, 2008
Creator: Karlsson, Niklas
Partner: UNT Libraries Government Documents Department
open access

Radiative B Meson Decay as a Probe of Physics Beyond the Standard Model: Time-Dependent CP Violation in B0 --> KS pi0 gamma and the B --> phi K gamma Branching Fraction

Description: The author presents measurements of radiative B meson decays to the final states K{sub s}{sup 0}{pi}{sup 0}{gamma} and K{phi}{gamma} based on data collected at the {Upsilon}(4S) resonance with the BABAR detector at the PEP-II e{sup +}e{sup -} collider at SLAC. In a data sample of 467 million B{bar B} pairs, the time-dependent CP asymmetry in B{sup 0} {yields} K{sub s}{sup 0}{pi}{sup 0}{gamma} decays is measured in two regions of K{sub s}{sup 0}-{pi}{sup 0} invariant mass. In the K* region, 0.8 … more
Date: January 22, 2009
Creator: Tuggle, Joseph Marion, IV
Partner: UNT Libraries Government Documents Department
open access

A Search for B+ to K+ Nu Anti-Nu

Description: A search for the rare, flavour-changing neutral current decay B{sup +} {yields} K{sup +} {nu}{bar {nu}} is presented using 81.9 fb{sup -1} of data collected at the {Upsilon}(4S) resonance by the BABAR experiment. Signal candidate events are selected through the identification of a high momentum charged kaon and significant missing energy, where the companion B{sup -} in the event has decayed semileptonically via B{sup -} {yields} D{sup 0}{ell}{sup -}{bar {nu}} X and X is kinematically constrain… more
Date: January 16, 2008
Creator: Jackson, Paul D.
Partner: UNT Libraries Government Documents Department
open access

Tests of Enhanced Leading Order QCD in W Boson plus Jet Production in 1.96-TeV Proton-Antiproton Collisions

Description: The authors have studied the W + {ge} n jets process in Tevatron Run II experiment. The data used correspond to a total integrated luminosity of 72 pb{sup -1} taken from March 2002 through January 2003. The lowest order QCD predictions have been tested with a new prescription of the parton-jet matching, which allows to construct the enhanced LO phase space. According to this procedure, one gets unique results which do not depend on unphysical bias of kinematical cuts to avoid the collinear/infr… more
Date: January 1, 2004
Creator: Tsuno, Soushi
Partner: UNT Libraries Government Documents Department
open access

Design of a rural water provision system to decrease arsenic exposure in Bangladesh

Description: Researchers at the Lawrence Berkeley National Laboratory have invented ARUBA (Arsenic Removal Using Bottom Ash) a material that effectively and affordably removes high concentrations of arsenic from contaminated groundwater. The technology is cost-effective because the substrate?bottom ash from coal fired power plants?is a waste material readily available in South Asia. During fieldwork in four sub-districts ofBangladesh, ARUBA reduced groundwater arsenic concentrations as high as 680 ppb to be… more
Date: January 7, 2009
Creator: Mathieu, Johanna
Partner: UNT Libraries Government Documents Department
open access

Measurement of CP Content and Time-Dependent CP Violation in B0 --> D*+D*- Decays

Description: This dissertation presents the measurement of the Cp-odd fraction and time-dependent CP violation parameters for the B{sup 0} {yields} D*{sup +} D*{sup -} decay. These results are based on the full BABAR dataset of (467 {+-} 5) x 10{sup 6} B{bar B} pairs collected at the PEP-II B Factory at the Stanford Linear Accelerator Center. An angular analysis finds that the CP-odd fraction of the B{sup 0} {yields} D*{sup +} D*{sup -} decay is R{sub {perpendicular}} = 0.158 {+-} 0.028 {+-} 0.006, where th… more
Date: January 5, 2009
Creator: Anderson, Jacob M.
Partner: UNT Libraries Government Documents Department
open access

Measurements of Time-Dependent CP-Asymmetry Parameters in B Meson Decays to \eta^{\prime} K^0 and of Branching Fractions of SU(3) Related Modes with BaBar Experiment at SLAC

Description: In this thesis work we have measured the following upper limits at 90% of confidence level, for B meson decays (in units of 10{sup -6}), using a statistics of 465.0 x 10{sup 6} B{bar B} pairs: {Beta}(B{sup 0} {yields} {eta}K{sup 0}) < 1.6 {Beta}(B{sup 0} {yields} {eta}{eta}) < 1.4 {Beta}(B{sup 0} {yields} {eta}{prime}{eta}{prime}) < 2.1 {Beta}(B{sup 0} {yields} {eta}{phi}) < 0.52 {Beta}(B{sup 0} {yields} {eta}{omega}) < 1.6 {Beta}(B{sup 0} {yields} {eta}{prime}{phi}) < 1.2 {Be… more
Date: January 22, 2009
Creator: Biassoni, Pietro & U., /Milan
Partner: UNT Libraries Government Documents Department
open access

Measurement of the Top Quark Mass using Dilepton Events and a Neutrino Weighting Algorithm with the D0 Experiment at the Tevatron (Run II)

Description: Elementary particle physics raises questions that are several thousand years old. What are the fundamental components of matter and how do they interact? These questions are linked to the question of what happened in the very first moments after the creation of the universe. Modern physics systematically tests nature to find answers to these and other fundamental questions. Precise theories are developed that describe various phenomena and at the same time are reduced to a few basic principals … more
Date: January 1, 2007
Creator: Meyer, Joerg
Partner: UNT Libraries Government Documents Department
open access

Determination of W boson helicity fractions in top quark decays in p anti-p collisions at CDF Run II and production of endcap modules for the ATLAS Silicon Tracker

Description: The thesis presented here includes two parts. The first part discusses the production of endcap modules for the ATLAS SemiConductor Tracker at the University of Geneva. The ATLAS experiment is one of the two multi-purpose experiments being built at the LHC at CERN. The University of Geneva invested extensive efforts to create an excellent and efficient module production site, in which 655 endcap outer modules were constructed. The complexity and extreme requirements for 10 years of LHC operatio… more
Date: January 1, 2007
Creator: Moed, Shulamit & U., /Geneva
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

The Cryogenic Dark Matter Search and Background Rejection with Event Position Information

Description: Evidence from observational cosmology and astrophysics indicates that about one third of the universe is matter, but that the known baryonic matter only contributes to the universe at 4%. A large fraction of the universe is cold and non-baryonic matter, which has important role in the universe structure formation and its evolution. The leading candidate for the non-baryonic dark matter is Weakly Interacting Massive Particles (WIMPs), which naturally occurs in the supersymmetry theory in particl… more
Date: January 1, 2005
Creator: Wang, Gen-sheng & U., /Case Western Reserve
Partner: UNT Libraries Government Documents Department
open access

Measurements of the Top Quark Pair Production Cross Section in Lepton + Jets Final States using a Topological Multivariate Technique as well as Lifetime b-Tagging in Proton - Anti-proton Collisions at s**(1/2)=1.96 TeV with the D0 Detector at the Tevatron

Description: Two alternative measurements of the t{bar t} production cross section at {radical}s = 1.96 TeV in proton-antiproton collisions in the lepton+jets channel are presented. The t{bar t} production cross section is extracted by combining the kinematic event information in a multivariate discriminant. The measurement yields {sigma}{sub p{bar p} {yields} t{bar t} + x} = 5.13{sub -1.57}{sup +1.76}(stat){sub -1.10}{sup +0.96}(syst) {+-} 0.33 (lumi) pb in the muon+jets channel, using 229.1 pb{sup -1}, an… more
Date: January 1, 2005
Creator: Golling, Tobias F.
Partner: UNT Libraries Government Documents Department
open access

Monte Carlo Simulations for Homeland Security Using Anthropomorphic Phantoms

Description: A radiological dispersion device (RDD) is a device which deliberately releases radioactive material for the purpose of causing terror or harm. In the event that a dirty bomb is detonated, there may be airborne radioactive material that can be inhaled as well as settle on an individuals leading to external contamination.
Date: January 1, 2008
Creator: Burns, Kimberly A.
Partner: UNT Libraries Government Documents Department
Back to Top of Screen