Inertial Conference Fusion Semiannual Report October 1999 - March 2000, Volume 1, Number 1 (open access)

Inertial Conference Fusion Semiannual Report October 1999 - March 2000, Volume 1, Number 1

This first issue of the ''ICF Semiannual Report'' contains articles whose diverse subjects attest to the broad technical and scientific challenges that are at the forefront of the ICF program at LLNL. The first article describes the progress being made at solving the surface roughness problem on capsule mandrels. All NIF capsule options, except machined beryllium, require a mandrel upon which the ablator is deposited. This mandrel sets the baseline sphericity of the final capsule. Problems involving defects in the mandrel have been overcome using various techniques so that 2-mm-size mandrels can now be made that meet the NIF design specification. The second article validates and provides a detailed numerical investigation of the shadowgraph technique currently used to diagnose the surface roughness of a fuel ice layer inside of a transparent capsule. It is crucial for the success of the indirect-drive ignition targets that the techniques used to characterize ice-surface roughness be well understood. This study identifies methods for analyzing the bright band that give an accurate measure of the ice-surface roughness. The third article describes a series of realistic laser and target modifications that can lead to 3-4 times more energy coupling and 10 times greater yield from a …
Date: March 1, 2000
Creator: Hammel, B. A.
System: The UNT Digital Library
Lasershot peening--a means to strengthen metals (open access)

Lasershot peening--a means to strengthen metals

Lasershot peening is an emerging modern process that impresses a compressive stress into the surfaces of metals, improving their operational lifetime. Almost everyone is familiar with taking a strip of metal or a wire and bending it multiple times until it breaks. In this situation, when the metal is bent, the surface of outer radius is stretched into a tensile state. Under tension, any flaw or micro-crack will grow in size with each bending of the metal until the crack grows through the entire strip, breaking it into two pieces. Flexure of metal components occurs in most applications. The teeth of a transmission gear flex as they deliver torque in a vehicle. Springs and valves flex every time they transfer loads. If fatigue failure from flexing occurs in the tooth of a transmission gear of light or heavy vehicles, in a fan blade of a diesel engine, in shock-absorbers or safety-related supporting structures, significant loss of assets and potentially loss of human life occurs. Lasershot peening, better than any other technique, has the potential to extend the fatigue lifetime of metal components. In the process, the laser generates a high intensity shock wave at the surface of the metal, straining …
Date: March 1, 2000
Creator: Chen, H. L.
System: The UNT Digital Library
Interfacial and near interfacial crack growth phenomena in metal bonded alumina (open access)

Interfacial and near interfacial crack growth phenomena in metal bonded alumina

Metal/ceramic interfaces can be found in many engineering applications including microelectronic packaging, multi-layered films, coatings, joints, and composite materials. In order to design reliable engineering systems that contain metal/ceramic interfaces, a comprehensive understanding of interfacial and near interfacial failure mechanisms is necessary.
Date: March 1, 2002
Creator: Kruzic, Jamie Joseph
System: The UNT Digital Library
Study of the Delta (1232) Using Double Polarization Asymmetries (open access)

Study of the Delta (1232) Using Double Polarization Asymmetries

An extensive experimental program to measure the spin structure of the nucleus is underway in Hall B at Jefferson Lab using a polarized electron beam incident on a polarized target. Spin degrees of freedom offer the possibility to test, in an independent way, existing models of resonance electro-production. The present analysis selects the Delta{sup +} (1232) in the exclusive channel {rvec p}({rvec e}, e'p)pi{sup 0} from data of the EG1 run period, taken in the Fall of 1998, to extract single and double asymmetries in a Q{sup 2} range from 0.5 to 1.5 GeV{sup 2}/c{sup 2}. Results of the asymmetries are presented as a function of momentum transfer Q{sup 2}. A comparison with the Effective Lagrangian Model by R. Davidson and N. Mukhopadhyay, the unitary isobar model MAID, and the dynamic model by Sato and Lee was performed. The data were found to be generally in good agreement with the models and a x{sup 2} comparison preferred the Sato-Lee model, which is tailored for the Delta (1232) photo- and electro-production. The present results are the first measurement of asymmetries for the exclusive reaction {rvec p}({rvec e}, e'p)pi{sup 0} and will provide new constraints for the models.
Date: March 1, 2002
Creator: Biselli, Angela
System: The UNT Digital Library
Mass spectrum analysis of K- pi+ from the semileptonic decay D+ --> K- pi+ mu+ nu (open access)

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

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} collision data, collected from Run II of the Fermilab Tevatron using the D0 detector, are analyzed. In the absence of a signal, values of tan {beta} > 80-120 are excluded at 95% Confidence Level (C.L.), depending on the (CP-odd) neutral Higgs boson mass (studied from 100 to 150 GeV/c{sup 2}).
Date: March 1, 2004
Creator: Massafferri Rodrigues, Andre & /Rio de Janeiro, CBPF
System: The UNT Digital Library
Measurement of the Ratio of Branching Fractions Br(Bs -> Ds- pi+)/Br(B -> D- pi+) at CDF-II (open access)

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

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 available for the measurement of B{sub s}{sup 0} mixing at CDF-II. They analyze 115 pb{sup -1} of data collected with the CDF-II detector in p{bar p} collisions at {radical}s = 1.96 TeV using a novel displaced track trigger. They reconstruct 78 {+-} 11 B{sub s}{sup 0} {yields} D{sub s}{sup -}{pi}{sup +} decays at 1153 {+-} 45 B{sup 0} {yields} D{sup -}{pi}{sup +} decays with good signal to background ratio. This is the world's largest sample of fully reconstructed B{sub s}{sup 0} {yields} D{sub s}{sup -}{pi}{sup +} decays. They find the ratio of production fractions multiplied by the ratio of branching fractions to be: f{sub s}/f{sub d} {center_dot} Br(B{sub s}{sup 0} {yields} D{sub s}{sup -}{pi}{sup +})/Br(B{sup 0} {yields} D{sup -}{pi}{sup +}) = 0.325 {+-} …
Date: March 1, 2004
Creator: Furic, Ivan Kresimir
System: The UNT Digital Library
p{sup 0} Meson Photoproduction using Linearly Polarized Photons with the CLAS detector (open access)

p{sup 0} Meson Photoproduction using Linearly Polarized Photons with the CLAS detector

The work presented in this thesis describes the first experimental measurement of the photon asymmetry of the exclusive {rvec {gamma}} {yields} {rho}{sup 0}p {yields} {pi}{sup +}{pi}{sup -}p reaction. The data were gathered during the summer of 2001 as a proof of principle study using a polarized beam of photons with the CLAS detector in Hall B of Jefferson Lab for the first time. The aim of the g8a set of experiments is to improve the understanding of the underlying symmetry of the quark degrees of freedom in the nucleon, the nature of the parity exchange between the incident photon and the target nucleon, the mechanism of associated strangeness production in electromagnetic reactions, and to search for evidence for the existence of the so called missing resonances. A beam of tagged and collimated linearly polarized photons (energy range 1.8-2.2 GeV) in conjunction with the large solid angle coverage of CLAS make possible the extraction of polarization observables for the photoproduction of vector mesons. For example, the azimuthal distribution of the {rho}{sup 0} as a function of its polar angle in the ({rvec {gamma}},p) c.m. system enables the measurement of the photon asymmetry parameter, {Sigma}. This has been measured for {theta}{sub c.m.} …
Date: March 1, 2004
Creator: Gordon, Chris
System: The UNT Digital Library
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 (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

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 leptoquark signal region, 124 events were observed with 118.3 {+-} 14.5 expected from background. Therefore, no evidence for leptoquark production was observed, and limits were set on the cross section times the squared branching ratio. Using the next-to-leading order cross section for leptoquark production, they excluded the mass interval 78 to 117 GeV/c{sup 2} at the 95% confidence level for 100% branching ratio into neutrino plus quark.
Date: March 1, 2004
Creator: Tsybychev, Dmitri
System: The UNT Digital Library
Search for New Physics in Dielectron Events in 1.96-TeV Proton - Anti-proton Collisions (open access)

Search for New Physics in Dielectron Events in 1.96-TeV Proton - Anti-proton Collisions

The authors have searched for new physics beyond the Standard Model of elementary particle physics in dielectron decay mode at the CDF (Collider Detector at Fermilab) experiment in {bar p}p collisions at {radical}s = 1.96 TeV. The data were collected during the 2002-2003 runs corresponding to an integrated luminosity of 200 pb{sup -1}. Many extensions of the Standard Model have been proposed. Grand Unified Theories (GUT) assumes a larger gauge symmetry group and predict new gauge bosons. GUT has hierarchy problem in it and there have been many attempts to solve the hierarchy problem. Solutions for the hierarchy problem are supersymmetry, technicolor, large extra dimensions, warped extra dimensions and little Higgs models. The authors analyze the differential distribution of dielectron events in terms of their invariant mass and no significant excess is found in very high mass region. They present a 95% confidence level limit on the production cross section times branching ratio for new resonant particles decaying into an electron pair as a function of invariant mass. New resonant particles include new neutral gauge boson Z', Randall-Sundrum graviton, R-parity violating sneutrino, and technicolor particles. They also present limits on the effective Planck scale of large extra dimensions.
Date: March 1, 2004
Creator: Ikado, Koji & U., /Waseda
System: The UNT Digital Library
Spatially indirect excitons in coupled quantum wells (open access)

Spatially indirect excitons in coupled quantum wells

Microscopic quantum phenomena such as interference or phase coherence between different quantum states are rarely manifest in macroscopic systems due to a lack of significant correlation between different states. An exciton system is one candidate for observation of possible quantum collective effects. In the dilute limit, excitons in semiconductors behave as bosons and are expected to undergo Bose-Einstein condensation (BEC) at a temperature several orders of magnitude higher than for atomic BEC because of their light mass. Furthermore, well-developed modern semiconductor technologies offer flexible manipulations of an exciton system. Realization of BEC in solid-state systems can thus provide new opportunities for macroscopic quantum coherence research. In semiconductor coupled quantum wells (CQW) under across-well static electric field, excitons exist as separately confined electron-hole pairs. These spatially indirect excitons exhibit a radiative recombination time much longer than their thermal relaxation time a unique feature in direct band gap semiconductor based structures. Their mutual repulsive dipole interaction further stabilizes the exciton system at low temperature and screens in-plane disorder more effectively. All these features make indirect excitons in CQW a promising system to search for quantum collective effects. Properties of indirect excitons in CQW have been analyzed and investigated extensively. The experimental results …
Date: March 1, 2004
Creator: Lai, Chih-Wei Eddy
System: The UNT Digital Library
Development of vertexing and lifetime triggers and a study of B(s) mixing using hadronic decays at D0 (open access)

Development of vertexing and lifetime triggers and a study of B(s) mixing using hadronic decays at D0

The D0 detector underwent a major upgrade to maximize its ability to fully exploit Run II at the Fermilab Tevatron, the world's highest energy collider. The upgrade included a completely new central tracking system with an outer scintillating fiber tracker and an inner silicon vertex detector all within a 2T superconducting solenoid. This thesis describes the development of high level trigger algorithms including vertexing, impact parameter significance and invariant mass, that utilize tracks from these detectors. One of the main physics goals of Run II is the observation of B{sub s} oscillations. This measurement, which cannot be performed at the B factories, will significantly constrain the ''unitarity triangle'' associated with Cp violation and so probe the Standard Model of particle physics. Furthermore this is an interesting measurement as the study of mixing in meson systems has a long history for revealing new physics. The second part of this thesis presents a study of the hadronic decay B{sub s} {yields} D{sub s}{pi}. This important mode provides the best proper time resolution for B{sub s} mixing and is reconstructed for the first time at D0. Projections on the sensitivity to B{sub s} oscillations are then presented.
Date: March 1, 2005
Creator: Barnes, Christopher P.
System: The UNT Digital Library
Measurement of the Top Quark Mass by Dynamical Likelihood Method using the Lepton plus Jets Events in 1.96 Tev Proton-Antiproton Collisions (open access)

Measurement of the Top Quark Mass by Dynamical Likelihood Method using the Lepton plus Jets Events in 1.96 Tev Proton-Antiproton Collisions

None
Date: March 1, 2005
Creator: Yorita, Kohei & U., /Waseda
System: The UNT Digital Library
Measurement of the Top Quark Mass with the Collider Detector at Fermilab (open access)

Measurement of the Top Quark Mass with the Collider Detector at Fermilab

None
Date: March 1, 2005
Creator: Sato, Koji
System: The UNT Digital Library
Measurement of W + gamma Production in the W to Muon Decay Channel in Proton - Anti-proton Collisions at s**(1/2) = 1.96-TeV (open access)

Measurement of W + gamma Production in the W to Muon Decay Channel in Proton - Anti-proton Collisions at s**(1/2) = 1.96-TeV

The production cross section and the kinematic properties of the decay products of W{gamma} in the W {yields} {mu}{nu} decay channel from p{bar p} collisions at {radical}s = 1.96 TeV are presented. The measurement use the high p{sub T} muon data from the upgraded Collider Detector at Fermilab (CDF). The data were collected between March 2002 and September 2003. The total integrated luminosities are 192 pb{sup -1} with the muon detector which covers the pseudorapidity region of |{eta}| {le} 0.6 and 175 pb{sup -1} with the muon detector covering the region 0.6 {le} |{eta}| {le} 1.0. In the Standard Model the {mu}{nu}{gamma} final states occur due to W{gamma} {yields} {mu}{nu}{gamma} production and via muon Bremsstrahlung, W {yields} {mu}{nu} {yields} {mu}{nu}{gamma}. W bosons are selected in their muon decay mode. Additionally, photons with transverse energy above 7 GeV, pseudorapidity in the central region (|{eta}| < 1.1) and muon-photon angular separation {Delta}R({mu},{gamma}) > 0.7 are selected. The author observes a total of 128 W{gamma} candidates, whereas the Standard Model expectation is 142.4 {+-} 9.5 events. The W{gamma} production cross section is found to be {sigma}(p{bar p} {yields} {mu}{nu}{gamma}) = 16.3 {+-} 2.3(stat.) {+-} 1.8(syst.) {+-} 1.2(lum.) [pb]. The theoretical prediction for this …
Date: March 1, 2005
Creator: Tanimoto, Naho & U., /Okayama
System: The UNT Digital Library
Measurement of z0 gamma production in ppbar collisions at s**(1/2) = 1.96 TeV (open access)

Measurement of z0 gamma production in ppbar collisions at s**(1/2) = 1.96 TeV

The cross-section of p{bar p} {yields} Z{sup 0}{gamma} + X production at {radical}s = 1.96 TeV using the CDF II detector at the Fermilab Tevatron is measured using 202 pb{sup -1} of data from March 2002 to September 2003, collected with high P{sub T} lepton triggers. The number of events observed and their kinematic distributions are compared to the NLO Standard Model prediction in both the Z{sup 0} {yields} e{sup +}e{sup -} and Z{sup 0} {yields} {mu}{sup +}{mu}{sup -} channels. For a minimum lepton-photon separation of {Delta}R{sub l{gamma}} > 0.7, E{sub T}{sup {gamma}} > 7 GeV and a dilepton invariant mass m(l,l) > 40 GeV/c{sup 2}, the cross-section times branching ratio is measured to be 4.6 {+-} 0.5(stat) {+-} 0.2(sys) {+-} 0.3(lumi) pb compared to the NLO Standard Model prediction of 4.5 {+-} 0.3(th) pb.
Date: March 1, 2005
Creator: Hayward, Helen Sarah
System: The UNT Digital Library
Search for the Higgs Boson Using High-pT Isolated Like-Sign Dil Events in 1.96-TeV Proton-Antiproton Collisions (open access)

Search for the Higgs Boson Using High-pT Isolated Like-Sign Dil Events in 1.96-TeV Proton-Antiproton Collisions

Our physics objective is to search for the neutral on using events containing a like-sign dilepton pair in the following reaction: q{bar q} {yields} W{sup {+-}} H {yields} W{sup {+-}} W*W* {yields} {ell}{sup {+-}}{ell}{sup {+-}} + X. The relevant Higgs boson mass region is above 160 GeV/c{sup 2} for the Standard Model Higgs boson where the branching fraction of H {yields} W*W* supersedes that of H {yields} b{bar b}. The search for this signature in the region at low mass (less than 135 GeV/c{sup 2}) is, however, still important because we need to investigate various Higgs boson couplings as an essential test to convince that signals are attributed to the Higgs boson production. This channel also covers the case beyond the Standard Model that the Higgs boson couples only to the gauge bosons, which is referred to as the bosophilic or fermiophobic Higgs boson. The corresponding mass region suitable to our signature is above 110 GeV/c{sup 2} where the branching fraction of H {yields} {gamma}{gamma} is overtaken by this channel. On the experimental side, the like-sign dilepton event is one of the cleanest signature in hadron collisions. This analysis exploiting such a distinctive signature is therefore expected to have a …
Date: March 1, 2005
Creator: Kobayashi, Hirokazu
System: The UNT Digital Library
Measurement of b-quark Jet Shapes at CDF (open access)

Measurement of b-quark Jet Shapes at CDF

The main topic of this thesis is the measurement of b-quark jet shapes at CDF. CDF is an experiment located at Fermilab, in the United States, which studies proton-antiproton collisions at a center of mass energy of 1.96TeV. To reach this energy, the particles are accelerated using the Tevatron accelerator which is currently the highest energy collider in operation. The data used for this analysis were taken between February 2002 and September 2004 and represent an integrated luminosity of about 300 pb{sup -1}. This is the first time that b-quark jet shapes have been measured at hadron colliders. The basis of this measurement lies in the possibility of enhancing the b-quark jet content of jet samples by requiring the jets to be identified as having a displaced vertex inside the jet cone. Such jets are called tagged. This enhances the b-quark jet fraction from about 5% before tagging to 20-40% after tagging, depending on the transverse momentum of the jets. I verified that it is possible to apply this secondary vertex tagging algorithm to different cone jet algorithms (MidPoint and JetClu) and different cone sizes (0.4 and 0.7). I found that the performance of the algorithm does not change significantly, …
Date: March 1, 2006
Creator: Lister, Alison
System: The UNT Digital Library
Measurement of J/psi meson and b-hadron production cross section at sqrt(s) = 1.96 TeV (open access)

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

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. The fraction of J/{psi} events from the decay of the long-lived b-hadrons is separated by using the lifetime distribution in all events with p{sub T}(J/{psi}) > 1.25 GeV/c. The total cross section for b-hadrons, including both hadrons and anti-hadrons, decaying to J/{psi} with transverse momenta greater than 1.25 GeV/c in the rapidity range |y(J/{psi})| < 0.6, is found to be 0.330 {+-} 0.005(stat){sub -0.033}{sup +0.036}(syst) {mu}b. Using a Monte Carlo simulation of the decay kinematics of b-hadrons to all final states containing a J/{psi}, the first measurement of the total single b-hadron cross section down to zero transverse momentum is extracted at sqrts = 1960 GeV. The total single b-hadron cross section integrated over all transverse momenta for b-hadrons in the rapidity …
Date: March 1, 2006
Creator: Yamashita, Tomohiro & U., /Okayama
System: The UNT Digital Library
Measurement of the strange - antistrange asymmetry at NLO in QCD from NuTeV dimuon data (open access)

Measurement of the strange - antistrange asymmetry at NLO in QCD from NuTeV dimuon data

A measurement of the asymmetry between the strange and antistrange quark distributions, from a next to leading order QCD analysis of dimuon events measured by the NuTeV experiment at Fermilab is presented. Neutrino charged current events with two muons in the final state provide a direct means for studying charm production and measuring the strange sea. NuTeV's sign selected beam allows independent measurement of the strange and antistrange seas. An improved measurement of the neutrino and antineutrino forward dimuon cross section tables, using the complete charged current event sample for normalization is performed. These tables are then analyzed at NLO to measure the strange and antistrange seas. Detector acceptance is modeled using an NLO charm cross section differential in all variables required. The strange quark distribution is found to have an integrated momentum weighted asymmetry of +0.00196 {+-} 0.00046(stat) {+-} 0.00045(syst) {+-} 0.00182(external). The charm mass is found to be 1.41 {+-} 0.10(stat) {+-} 0.08(syst) {+-} 0.12(external) GeV.
Date: March 1, 2006
Creator: Mason, David Alexander & U., /Oregon
System: The UNT Digital Library
Measurement of the Top Quark Pair Production Cross Section in p anti-p collisions at s**(1/2) = 1.96 TeV (open access)

Measurement of the Top Quark Pair Production Cross Section in p anti-p collisions at s**(1/2) = 1.96 TeV

None
Date: March 1, 2006
Creator: Otero y Garzon, Gustavo J.
System: The UNT Digital Library
Pipeline Structural Health Monitoring Using Macro-fiber Composite Active Sensors (open access)

Pipeline Structural Health Monitoring Using Macro-fiber Composite Active Sensors

The United States economy is heavily dependent upon a vast network of pipeline systems to transport and distribute the nation's energy resources. As this network of pipelines continues to age, monitoring and maintaining its structural integrity remains essential to the nation's energy interests. Numerous pipeline accidents over the past several years have resulted in hundreds of fatalities and billions of dollars in property damages. These accidents show that the current monitoring methods are not sufficient and leave a considerable margin for improvement. To avoid such catastrophes, more thorough methods are needed. As a solution, the research of this thesis proposes a structural health monitoring (SHM) system for pipeline networks. By implementing a SHM system with pipelines, their structural integrity can be continuously monitored, reducing the overall risks and costs associated with current methods. The proposed SHM system relies upon the deployment of macro-fiber composite (MFC) patches for the sensor array. Because MFC patches are flexible and resilient, they can be permanently mounted to the curved surface of a pipeline's main body. From this location, the MFC patches are used to monitor the structural integrity of the entire pipeline. Two damage detection techniques, guided wave and impedance methods, were implemented as …
Date: March 1, 2006
Creator: Thien, Andrew B.
System: The UNT Digital Library
Inclusive jet production studies at the Tevatron using the CDF detector (open access)

Inclusive jet production studies at the Tevatron using the CDF detector

Quantum Chromodynamics (QCD) is the gauge theory that governs the strong interactions between quarks and gluons inside hadrons like, for example, protons and neutrons. It shows two well established characteristics, related to the non-Abelian nature of the theory, that dominate its phenomenology: asymptotic freedom and color confinement. The dependence of the strong coupling, {alpha}{sub s}(Q{sup 2}), with the hard scale is such that it decreases with decreasing the distance between partons. This allows to perform precise theoretical calculations at large energy transfer (short distances) using perturbative QCD (pQCD). On the other hand, the strength of the interaction increases with the distance between partons and thus colored quarks and gluons are forced to be confined inside colorless hadrons.
Date: March 1, 2007
Creator: Norniella, Olga
System: The UNT Digital Library
Measurement of 1/sigma dsigma/dy for Z/gamma* ---> e+e- at s**(1/2) = 1.96 TeV (open access)

Measurement of 1/sigma dsigma/dy for Z/gamma* ---> e+e- at s**(1/2) = 1.96 TeV

The author presents the measurement of p{bar p} {yields} Z/{gamma}* {yields} e{sup +}e{sup -} + X inclusive differential cross section as a function of boson rapidity. The data, which correspond to an integrated luminosity of 0.4 fb{sup -1}, were collected with D0 detector at Tevatron p{bar p} collider. At the Run II energy of {radical}s = 1.96 TeV, Z bosons are produced with rapidity out to {+-} 3. The cross section is measured in a mass range between 71 to 111 GeV for the allowed kinematic range.
Date: March 1, 2007
Creator: Yan, Ming
System: The UNT Digital Library
Measurement of the ratio of branching fractions b(bs --> ds- ds+) /b (b0 --> d- ds+) with the CDF detector (open access)

Measurement of the ratio of branching fractions b(bs --> ds- ds+) /b (b0 --> d- ds+) with the CDF detector

In this thesis they report the measurement of ratios of branching fractions: {Beta}(B{sub s}{sup 0} {yields} D{sub s}{sup -}{pi}{sup +}{pi}{sup +}{pi}{sup -})/{Beta}(B{sup 0} {yields} D{sup -}{pi}{sup +}{pi}{sup +}{pi}{sup -}), and {Beta}(B{sup 0} {yields} D{sup -}D{sub s}{sup +})/{Beta}(B{sup 0} {yields} D{sup -}{pi}{sup +}{pi}{sup +}{pi}{sup -}), using 355 pb{sup -1} of data collected by CDF detector at the Tevatron p{bar p} collider at {radical}s = 1.96 TeV.
Date: March 1, 2007
Creator: Iyutin, Boris
System: The UNT Digital Library