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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

Grid Development and a Study of B-flavour tagging at D�

Description: Run IIa of the D0 experiment at the Tevatron took place between Spring 2002 and Spring 2006, collecting approximately 1.2 fb{sup -1} of data. A fundamental principal of the D0 computing model is the utilization of globally distributed computing resources as part of a grid. In particular use is made of the 'SAMGrid'. The first part of this thesis describes the work undertaken at Imperial College on several D0 distributed computing projects. These included the deployment and development of parts … more
Date: September 1, 2006
Creator: Lewis, Philip William
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

Nanocrystal Solar Cells

Description: This dissertation presents the results of a research agenda aimed at improving integration and stability in nanocrystal-based solar cells through advances in active materials and device architectures. The introduction of 3-dimensional nanocrystals illustrates the potential for improving transport and percolation in hybrid solar cells and enables novel fabrication methods for optimizing integration in these systems. Fabricating cells by sequential deposition allows for solution-based assembly of… more
Date: December 15, 2006
Creator: Gur, Ilan
Partner: UNT Libraries Government Documents Department
open access

Search for New Physics in the Jets + Missing ET topology

Description: Although the standard model of particle physics agrees perfectly with experimental data, it is unlikely the final theory describing particles and their interactions. New phenomena has been searched in the jets and missing transverse energy topology. Such phenomena may be due to the pair production of leptoquarks decaying into a quark and a neutrino or the pair production of stops decaying into a charm and a neutralino which is assumed to be the lightest supersymmetric particle. These searches h… more
Date: May 1, 2006
Creator: Makovec, Nikola Michel & /Orsay
Partner: UNT Libraries Government Documents Department
open access

QCD fits to neutrino-iron structure functions at NuTeV

Description: This thesis presents a new determination of {Lambda}{sub QCD} from Next-to-Leading Order QCD fits to the Q{sup 2} dependence of neutrino-iron structure functions. This is the first measurement of {Lambda}{sub QCD} which uses a theoretical model that fully accounts for heavy quark production. Compared with previous neutrino measurements, the result has improved understanding of the largest systematic uncertainties on the muon and hadron energy scales. These improvements lead to one of the most p… more
Date: August 1, 2006
Creator: Radescu, Voica A. & U., /Pittsburgh
Partner: UNT Libraries Government Documents Department
open access

Habilitation Thesis on STT and Higgs searches in WH Rroduction

Description: The detector of the D0 experiment at the proton anti-proton collider Tevatron in Run II is discussed in detail. The performance of the collider and the experiment is presented. Standard model Higgs searches with integrated luminosities between 260 pb{sup -1} and 950 pb{sup -1} and their combination are performed. No deviation from SM background expectation has been observed. Sensitivity prospects at the Tevatron are shown.
Date: December 1, 2006
Creator: Sonnenschein, Lars
Partner: UNT Libraries Government Documents Department
open access

Search for Higgs boson production in proton-antiproton collisions at s**(1/2) = 1.96 TeV

Description: We performed a search for Standard Model Higgs boson production in association with W boson (p{bar p} {yields} W{sup {+-}}H {yields} {ell}{nu}b{bar b}) in p{bar p} collisions at {radical}s = 1.96 TeV. The search uses the data collected between February 2002 and February 2006 at Collider Detector at Fermilab (CDF), which corresponds to an integrated luminosity of about 1 fb{sup -1}. The experimental final state of WH {yields} {ell}{nu}b{bar b} process is lepton (e{sup {+-}}/{mu}{sup {+-}}), miss… more
Date: December 1, 2006
Creator: Kusakabe, Yoshiaki & U., /Waseda
Partner: UNT Libraries Government Documents Department
open access

Diffractive processes in antiproton-proton collision at s**(1/2) = 1.96 TeV in the D0 experiment

Description: A first study of single diffractive central high-p{sub T} dijet events in p{bar p} collisions at center-of-mass energy {radical}s = 1.96 TeV is presented, using data recorded by the D0 detector at the Tevatron during RunIIa in 2002-2004. The total integrated luminosity corresponding to the data sample is 398 pb{sup -1}. A diffractive sample is selected using a rapidity gap approach. A precise definition of the rapidity gap constitutes the first part of the thesis. The rapidity gap is defined by… more
Date: September 1, 2006
Creator: Otec, Roman & /Prague, Tech. U.
Partner: UNT Libraries Government Documents Department
open access

The ^2H(e,e'p)n Reaction at High Four-Momentum Transfer

Description: This dissertation presents the highest four-momentum transfer, Q^2,quasielastic (x_Bj = 1) results from Experiment E01-020 which systematically explored the 2He(e,e'p)n reaction ("Electro-disintegration" of the deuteron) at three different four-momentum transfers, Q^2 = 0.8, 2.1, and 3.5 GeV^2 and missing momenta, P_miss = 0, 100, 200, 300, 400, and 500 GeV including separations of the longitudinal-transverse interference response function, R_LT, and extractoin of the longitudinal-transverse as… more
Date: December 31, 2006
Creator: Ibrahim, Hassan
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

A Search for the Production of Technicolor Particles at the D-Zero Detector

Description: A search for the Technicolor processes p{bar p} {yields} {rho}{sub T}{sup {+-}} {yields} W{sup {+-}}{pi}{sub T}{sup 0} {yields} {mu}{nu}b{bar b} and p{bar p} {yields} {rho}{sub T}{sup 0} {yields} W{sup {+-}}{pi}{sub T}{sup {+-}} {yields} {mu}{nu}b{bar c} is conducted at the D0 detector. Selection requirements are individually optimized for each of twenty mass hypotheses by means of a random grid search. No excess is seen in a 291 pb{sup -1} data set and 95% confidence level upper limits are set… more
Date: July 1, 2006
Creator: Desai, Satish Vijay
Partner: UNT Libraries Government Documents Department
open access

Design of a boron neutron capture enhanced fast neutron therapy assembly

Description: The use of boron neutron capture to boost tumor dose in fast neutron therapy has been investigated at several fast neutron therapy centers worldwide. This treatment is termed boron neutron capture enhanced fast neutron therapy (BNCEFNT). It is a combination of boron neutron capture therapy (BNCT) and fast neutron therapy (FNT). It is believed that BNCEFNT may be useful in the treatment of some radioresistant brain tumors, such as glioblastoma multiform (GBM). A boron neutron capture enhanced fa… more
Date: August 1, 2006
Creator: Wang, Zhonglu & Tech, /Georgia
Partner: UNT Libraries Government Documents Department
open access

A Measurement of the Top Quark Mass in the Dilepton Decay Channel at CDF II

Description: The top quark, the most recently discovered quark, is the most massive known fundamental fermion. Precision measurements of its mass, a free parameter in the Standard Model of particle physics, can be used to constrain the mass of the Higgs Boson. In addition, deviations in the mass as measured in different channels can provide possible evidence for new physics. We describe a measurement of the top quark mass in the decay channel with two charged leptons, known as the dilepton channel, using da… more
Date: August 1, 2006
Creator: Jayatilaka, Bodhitha A.
Partner: UNT Libraries Government Documents Department
open access

Nanolithographic Fabrication and Heterogeneous Reaction Studies ofTwo-Dimensional Platinum Model Catalyst Systems

Description: In order to better understand the fundamental components that govern catalytic activity, two-dimensional model platinum nanocatalyst arrays have been designed and fabricated. These catalysts arrays are meant to model the interplay of the metal and support important to industrial heterogeneous catalytic reactions. Photolithography and sub-lithographic techniques such as electron beam lithography, size reduction lithography and nanoimprint lithography have been employed to create these platinum n… more
Date: May 20, 2006
Creator: Contreras, A.M.
Partner: UNT Libraries Government Documents Department
open access

Ligand Rearrangements of Organometallic Complexes inSolution

Description: Many chemical reactions utilize organometallic complexes as catalysts. These complexes find use in reactions as varied as bond activation, polymerization, and isomerization. This thesis outlines the construction of a new ultrafast laser system with an emphasis on the generation of tunable mid-infrared pulses, data collection, and data analysis.
Date: May 8, 2006
Creator: Shanoski, Jennifer E.
Partner: UNT Libraries Government Documents Department
open access

Resolution Improvement and Pattern Generator Development for theMaskless Micro-Ion-Beam Reduction Lithography System

Description: The shrinking of IC devices has followed the Moore's Law for over three decades, which states that the density of transistors on integrated circuits will double about every two years. This great achievement is obtained via continuous advance in lithography technology. With the adoption of complicated resolution enhancement technologies, such as the phase shifting mask (PSM), the optical proximity correction (OPC), optical lithography with wavelength of 193 nm has enabled 45 nm printing by immer… more
Date: May 18, 2006
Creator: Jiang, Ximan
Partner: UNT Libraries Government Documents Department
open access

Study of collisons of supersymmetric top Quark in the channel stop anti-stop -> e+- mu-+ sneutrino anti-sneutrino b anti-b with the experience of D0 at the Tevatron. Callibration of the electromagnetic calorimeter at D0.

Description: Supersymmetry is one of the most natural extensions of the Standard Model. At low energy it may consist in the Minimal Supersymmetric Standard Model which is the framework chosen to perform the search of the stop with 350 pb{sup -1} of data collected by D0 during the RunIIa period of the TeVatron. They selected the events with an electron, a muon, missing transverse energy and non-isolated tracks, signature for the stop decay in 3-body ({bar t} {yields} bl{bar {nu}}). Since no significant exces… more
Date: October 1, 2006
Creator: Mendes, Aurelien & /Marseille U., Luminy
Partner: UNT Libraries Government Documents Department
open access

Excited State Structural Dynamics of Carotenoids and ChargeTransfer Systems

Description: This dissertation describes the development andimplementation of a visible/near infrared pump/mid-infrared probeapparatus. Chapter 1 describes the background and motivation ofinvestigating optically induced structural dynamics, paying specificattention to solvation and the excitation selection rules of highlysymmetric molecules such as carotenoids. Chapter 2 describes thedevelopment and construction of the experimental apparatus usedthroughout the remainder of this dissertation. Chapter 3 will … more
Date: September 1, 2006
Creator: Van Tassle, Aaron Justin
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

Nanoscale chemical and mechanical characterization of thin films:sum frequency generation (SFG) vibrational spectroscopy at buriedinterfaces

Description: Sum frequency generation (SFG) surface vibrational spectroscopy was used to characterize interfaces pertinent to current surface engineering applications, such as thin film polymers and novel catalysts. An array of advanced surface science techniques like scanning probe microscopy (SPM), x-ray photoelectron spectroscopy (XPS), gas chromatography (GC) and electron microscopy were used to obtain experimental measurements complementary to SFG data elucidating polymer and catalyst surface compositi… more
Date: May 19, 2006
Creator: Kweskin, S.J.
Partner: UNT Libraries Government Documents Department
open access

M dwarfs in the Local Milky Way: The Field Low-Mass Stellar Luminosity and Mass Functions

Description: Modern sky surveys, such as the Sloan Digital Sky Survey (SDSS) and the Two-Micron All Sky Survey, have revolutionized how Astronomy is done. With millions of photometric and spectroscopic observations, global observational properties can be studied with unprecedented statistical significance. Low-mass stars dominate the local Milky Way, with tens of millions observed by SDSS within a few kpc. Thus, they make ideal tracers of the Galactic potential, and the thin and thick disks. In this thesis … more
Date: June 1, 2006
Creator: Bochanski, John J., Jr. & /Washington U., Seattle, Astron. Dept.
Partner: UNT Libraries Government Documents Department
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