Measurement of D0 - Anti-D0 Mixing With a Time-Dependent Amplitude Analysis of D0 \rightarrow K+ Pi- Pi0 (open access)

Measurement of D0 - Anti-D0 Mixing With a Time-Dependent Amplitude Analysis of D0 \rightarrow K+ Pi- Pi0

None
Date: June 10, 2013
Creator: Pelliccioni, Mario & U., /Turin
System: The UNT Digital Library
Search for CP violation in singly Cabibbo suppressed four-body D decays (open access)

Search for CP violation in singly Cabibbo suppressed four-body D decays

We search for CP violation in a sample of 4.7 x 10{sup 4} singly Cabibbo suppressed D{sup 0} {yields} K{sup +} K{sup -} {pi}{sup +}{pi}{sup -} decays and 1.8(2.6) x 10{sup 4} D{sub (s)}{sup +} {yields} K{sub S}{sup 0} K{sup +} {pi}{sup +} {pi}{sup -} decays. CP violation is searched for in the difference between the T-odd asymmetries, obtained using triple product correlations, measured for D and {bar D} decays. The measured CP violation parameters are A{sub T}(D{sup 0}) = (1.0 {+-} 5.1(stat) {+-} 4.4(syst)) x 10{sup -3}, A{sub T}(D{sup +}) = (-11.96 {+-} 10.04(stat) {+-} 4.81(syst)) x 10{sup -3} and A{sub T}(D{sub s}{sup +}) = (-13.57 {+-} 7.67(stat) {+-} 4.82(syst)) x 10{sup -3}. This search for CP violation showed that the T-odd correlations are a powerful tool to measure the CP violating observable A{sub T}. The relative simplicity of an analysis based on T-odd correlations and the high quality results that can be obtained, allow to consider this tool as fundamental to search for CP violation in four-body decays. Even if the CP violation has not been found, excluding any New Physics effect to the sensitivity of about 0.5%, it is still worth to search for CP violation in …
Date: June 22, 2011
Creator: Martinelli, Maurizio & U., /Bari
System: The UNT Digital Library
A Measurement of the Exclusive Branching Fraction for B \to pi K at BaBar (open access)

A Measurement of the Exclusive Branching Fraction for B \to pi K at BaBar

None
Date: June 11, 2013
Creator: Aspinwall, L.
System: The UNT Digital Library
A Measurement of Neutral B Mixing using Di-Lepton Events with the BaBar Detector (open access)

A Measurement of Neutral B Mixing using Di-Lepton Events with the BaBar Detector

None
Date: June 11, 2013
Creator: Gunawardane, N.
System: The UNT Digital Library
Measurement of single-target spin asymmetries in the electroproduction of negative pions in the semi-inclusive deep inelastic reaction n{up_arrow}(e,e'{pi}{sup -})X on a transversely polarized {sup 3}He target (open access)

Measurement of single-target spin asymmetries in the electroproduction of negative pions in the semi-inclusive deep inelastic reaction n{up_arrow}(e,e'{pi}{sup -})X on a transversely polarized {sup 3}He target

The experiment E06010 measured the target single spin asymmetry (SSA) in the semiinclusive deep inelastic (SIDIS) n{up_arrow}(e, e'{pi}{sup -})X reaction with a transversely polarized {sup 3}He target as an e#11;ective neutron target. This is the very #12;rst independent measurement of the neutron SSA, following the measurements at HERMES and COMPASS on the proton and the deuteron. The experiment acquired data in Hall A at Je#11;erson Laboratory with a continuous electron beam of energy 5.9 GeV, probing the valence quark region, with x = 0.13 {rt_arrow} 0.41, at Q{sup 2} = 1.31 {rt_arrow} 3.1 GeV{sup 2}. The two contributing mechanisms to the measured asymmetry, viz, the Collins effect and the Sivers effect can be realized through the variation of the asymmetry as a function of the Collins and Sivers angles. The neutron Collins and Sivers moments, associated with the azimuthal angular modulations, are extracted from the measured asymmetry for the very #12;first time and are presented in this thesis. The kinematics of this experiment is comparable to the HERMES proton measurement. However, the COMPASS measurements on deuteron and proton are in the low-x region. The results of this experiment are crucial as the first step toward the extraction of quark transversity …
Date: June 1, 2010
Creator: Dutta, Chiranjib
System: The UNT Digital Library
Unorthodox theoretical methods (open access)

Unorthodox theoretical methods

The use of the ReaxFF force field to correlate with NMR mobilities of amine catalytic substituents on a mesoporous silica nanosphere surface is considered. The interfacing of the ReaxFF force field within the Surface Integrated Molecular Orbital/Molecular Mechanics (SIMOMM) method, in order to replicate earlier SIMOMM published data and to compare with the ReaxFF data, is discussed. The development of a new correlation consistent Composite Approach (ccCA) is presented, which incorporates the completely renormalized coupled cluster method with singles, doubles and non-iterative triples corrections towards the determination of heats of formations and reaction pathways which contain biradical species.
Date: June 20, 2012
Creator: Nedd, Sean
System: The UNT Digital Library
Study of |Vtd/Vts| Using a Sum of Exclusive B \to X Gamma Final States Reconstructed With the BaBar Detector (open access)

Study of |Vtd/Vts| Using a Sum of Exclusive B \to X Gamma Final States Reconstructed With the BaBar Detector

None
Date: June 11, 2013
Creator: Tibbetts, Mark James
System: The UNT Digital Library
Cellular membrane trafficking of mesoporous silica nanoparticles (open access)

Cellular membrane trafficking of mesoporous silica nanoparticles

This dissertation mainly focuses on the investigation of the cellular membrane trafficking of mesoporous silica nanoparticles. We are interested in the study of endocytosis and exocytosis behaviors of mesoporous silica nanoparticles with desired surface functionality. The relationship between mesoporous silica nanoparticles and membrane trafficking of cells, either cancerous cells or normal cells was examined. Since mesoporous silica nanoparticles were applied in many drug delivery cases, the endocytotic efficiency of mesoporous silica nanoparticles needs to be investigated in more details in order to design the cellular drug delivery system in the controlled way. It is well known that cells can engulf some molecules outside of the cells through a receptor-ligand associated endocytosis. We are interested to determine if those biomolecules binding to cell surface receptors can be utilized on mesoporous silica nanoparticle materials to improve the uptake efficiency or govern the mechanism of endocytosis of mesoporous silica nanoparticles. Arginine-glycine-aspartate (RGD) is a small peptide recognized by cell integrin receptors and it was reported that avidin internalization was highly promoted by tumor lectin. Both RGD and avidin were linked to the surface of mesoporous silica nanoparticle materials to investigate the effect of receptor-associated biomolecule on cellular endocytosis efficiency. The effect of ligand …
Date: June 21, 2012
Creator: Fang, I-Ju
System: The UNT Digital Library
Study of Charmless Semileptonic B Decays And a Measurement of the CKM Matrix Element |Vub| at BaBar (open access)

Study of Charmless Semileptonic B Decays And a Measurement of the CKM Matrix Element |Vub| at BaBar

None
Date: June 11, 2013
Creator: Taylor, G.P.
System: The UNT Digital Library
Investigation of the Charmless Decay B+- \rightarrow K+- K-+ K+- Using a Dalitz Plot Analysis at BaBar (open access)

Investigation of the Charmless Decay B+- \rightarrow K+- K-+ K+- Using a Dalitz Plot Analysis at BaBar

None
Date: June 10, 2013
Creator: Hart, Alistair Jepson & U., /Birmingham
System: The UNT Digital Library
Developing nanotechnology for biofuel and plant science applications (open access)

Developing nanotechnology for biofuel and plant science applications

This dissertation presents the research on the development of mesoporous silica based nanotechnology for applications in biofuels and plant science. Mesoporous silica nanoparticles (MSNs) have been the subject of great interest in the last two decades due to their unique properties of high surface area, tunable pore size and particle morphology. The robust nature of the silica framework is easily functionalized to make the MSNs a promising option for selective separations. Also, the independent channels that form the pores of MSN have been exploited in the use of particles as platforms for molecular delivery. Pore size and organic functionality are varied to identify the ideal adsorbent material for free fatty acids (FFAs). The resulting material is able to sequester FFAs with a high degree of selectivity from a simulated solution and microalgal oil. The recyclability and industrial implications are also explored. A continuation of the previous material, further tuning of MSN pore size was investigated. Particles with a smaller diameter selectively sequester polyunsaturated free fatty acids (PUFAs) over monounsaturated FFAs and saturated FFAs. The experimental results were verified with molecular modeling. Mesoporous silica nanoparticle materials with a pore diameter of 10 nm (MSN-10) were decorated with small gold nanoparticles. The …
Date: June 20, 2012
Creator: Valenstein, Justin
System: The UNT Digital Library
Correlation Femtoscopy of Hyperons Produced in Interactions of Hyperons with Nuclei with 600 GeV Energy (open access)

Correlation Femtoscopy of Hyperons Produced in Interactions of Hyperons with Nuclei with 600 GeV Energy

None
Date: June 1, 2010
Creator: Romanov, Dmitry
System: The UNT Digital Library
$H \to \gamma\gamma$ search and direct photon pair production differential cross section (open access)

$H \to \gamma\gamma$ search and direct photon pair production differential cross section

At a hadron collider, diphoton (γγ) production allows detailed studies of the Standard Model (SM), as well as as searches for new phenomena, such as new heavy resonances, extra spatial dimensions or cascade decays of heavy new particles. Within the SM, continuum γγ+X production is characterized by a steeply-falling γγ mass spectrum, on top of which a heavy resonance decaying into γγ can potentially be observed. In particular, this is considered one of the most promising discovery channels for a SM Higgs boson at the LHC, despite the small branching ratio of BR (H → γγ) {approx} 0.2% for 110 &lt; M<sub>Higgs</sub> &lt; 140 GeV. At the Tevatron, the dominant SM Higgs boson production mechanism is gluon fusion, followed by associated production with a W or Z boson, and vector boson fusion. While the SM Higgs production rate at the Tevatron is not sufficient to observe it in the γγ mode, the Hgg and Hγγ couplings, being loop-mediated, are particularly sensitive to new physics effects. Furthermore, in some models beyond the SM, for instance, fermiophobic Higgs, with no couplings to fermions, the BR (H → γγ) can be enhanced significantly relative to the SM prediction, while has the SM-like production …
Date: June 1, 2010
Creator: Bu, Xuebing
System: The UNT Digital Library
Measurement of the Forward-Backward Charge Asymmetry($A_{FB}$) using $p\bar{p}\rightarrow Z/\gamma*\rightarrow e^+e^-$ events in $\sqrt{S} = 1.96$ TeV (open access)

Measurement of the Forward-Backward Charge Asymmetry($A_{FB}$) using $p\bar{p}\rightarrow Z/\gamma*\rightarrow e^+e^-$ events in $\sqrt{S} = 1.96$ TeV

This dissertation describes a measurement of the forward-backward asymmetry(A<sub>FB</sub>) in p$\bar{p}$ → Z/γ* → ee events using 5.0 fb<sup>-1</sup> data collected by the D0 detector at the Fermilab Tevatron. The AFB is measured as a function of the invariant mass of the electron-positron pair. Along with obtaining normalized differential cross section 1/σ x dσ/dM and Z to light quark couplings, we measured the Standard Model(SM) fundamental parameter, the effective weak mixing angle sin<sup>2</sup> θ$lept\atop{eff}$, with an unprecedented precise in light quark sector, namely the single D0 measurement has surpassed the LEP combination of four experiment results of inclusive hadronic charge asymmetry.
Date: June 1, 2010
Creator: Yin, Hang
System: The UNT Digital Library
Resonance searches with the $t\overline{t}$ Invariant Mass Distribution measured with the D\O\, Experiment at $\sqrt{s}=1.96\,\textrm{TeV} (open access)

Resonance searches with the $t\overline{t}$ Invariant Mass Distribution measured with the D\O\, Experiment at $\sqrt{s}=1.96\,\textrm{TeV}

Understanding the universe, its birth and its future is one of the biggest motivations in physics. In order to understand the cosmos, the fundamental particles forming the universe, the components our matter is built of need to be known and understood. Over time physicists have built a theory which describes the physics of the known fundamental particles very well: the Standard Model (SM) of particle physics. The SM describes the particles, their interactions and phenomena with high precision. So far no proven deviations from the SM have been found, though recently evidence for possible physics beyond the SM has been observed. The SM is not describing the mass of the elementary particles however and even with the addition of the Higgs mechanism giving mass to the particles, we have no full theory for all four fundamental forces. We know the model needs to be extended or replaced by another one, as gravitation is not included in the SM. Having a theory which describes all fundamental particles found so far and all but one fundamental interaction is a great success. However, all this describes about 4% of the universe we live in. 23% is dark matter and 73% is dark energy. …
Date: June 1, 2010
Creator: Schliephake, Thorsten Dirk & U., /Wuppertal
System: The UNT Digital Library
SQUID magnetometry from nanometer to centimeter length scales (open access)

SQUID magnetometry from nanometer to centimeter length scales

The development of Superconducting QUantum Interference Device (SQUID)-based magnetometer for two applications, in vivo prepolarized, ultra-low field MRI of humans and dispersive readout of SQUIDs for micro- and nano-scale magnetometery, are the focus of this thesis.
Date: June 28, 2010
Creator: Hatridge, Michael J.
System: The UNT Digital Library
Electron Neutrino Appearance in the MINOS Experiment (open access)

Electron Neutrino Appearance in the MINOS Experiment

The MINOS experiment is a long-baseline neutrino oscillation experiment which sends a high intensity muon neutrino beam through two functionally identical detectors, a Near detector at the Fermi National Accelerator Laboratory in Illinois, 1km from the beam source, and a Far detector, 734km away, in the Soudan Mine in Minnesota. MINOS may be able to measure the neutrino mixing angle parameter sin{sup 2} 2{theta}{sub 13} for the first time. Detector granularity, however, makes it very hard to distinguish any {nu}{sub e} appearance signal events characteristic of a non-zero value of {theta}{sub 13} from background neutral current (NC) and short-track {nu}{sub {mu}} charged current (CC) events. Also, uncertainties in the hadronic shower modeling in the kinematic region characteristic of this analysis are relatively large. A new data-driven background decomposition method designed to address those issues is developed and its results presented. By removing the long muon tracks from {nu}{sub {mu}}-CC events, the Muon Removed Charge Current (MRCC) method creates independent pseudo-NC samples that can be used to correct the MINOS Monte Carlo to agree with the high-statistics Near detector data and to decompose the latter into components so as to predict the expected Far detector background. The MRCC method also provides …
Date: June 1, 2010
Creator: Holin, Anna Maria & London, /University Coll.
System: The UNT Digital Library
In Situ Studies of Surface Mobility on Noble Metal Model Catalysts Using STM and XPS at Ambient Pressure (open access)

In Situ Studies of Surface Mobility on Noble Metal Model Catalysts Using STM and XPS at Ambient Pressure

High Pressure Scanning Tunneling Microscopy (HP-STM) and Ambient Pressure X-ray Photoelectron Spectroscopy were used to study the structural properties and catalytic behavior of noble metal surfaces at high pressure. HP-STM was used to study the structural rearrangement of the top most atomic surface layer of the metal surfaces in response to changes in gas pressure and reactive conditions. AP-XPS was applied to single crystal and nanoparticle systems to monitor changes in the chemical composition of the surface layer in response to changing gas conditions. STM studies on the Pt(100) crystal face showed the lifting of the Pt(100)-hex surface reconstruction in the presence of CO, H<sub>2</sub>, and Benzene. The gas adsorption and subsequent charge transfer relieves the surface strain caused by the low coordination number of the (100) surface atoms allowing the formation of a (1 x 1) surface structure commensurate with the bulk terminated crystal structure. The surface phase change causes a transformation of the surface layer from hexagonal packing geometry to a four-fold symmetric surface which is rich in atomic defects. Lifting the hex reconstruction at room temperature resulted in a surface structure decorated with 2-3 nm Pt adatom islands with a high density of step edge sites. Annealing …
Date: June 1, 2010
Creator: Butcher, Derek Robert
System: The UNT Digital Library
Measurement of the Three-jet Mass Cross Section in $p\bar{p}$ Collisions at $\sqrt{s}=1.96$ TeV (open access)

Measurement of the Three-jet Mass Cross Section in $p\bar{p}$ Collisions at $\sqrt{s}=1.96$ TeV

This thesis describes the measurement of the inclusive three-jet cross section in proton-antiproton collisions at √s = 1.96 TeV measured at the D0 experiment at the Fermilab Tevatron Collider in the Fermi National Accelerator Laboratory, Batavia, Illinois, USA. The cross section as a function of three-jet invariant mass is provided in three regions of the third jet transverse momentum and three regions of jet rapidities. It utilizes a data sample collected in the so called Run IIa data taking period (2002-2006) corresponding to the integrated luminosity of about 0.7 fb<sup>-1</sup>. The results are used to test the next-to-leading order predictions of Quantum chromodynamics computed using the latest parton distribution functions.
Date: June 1, 2010
Creator: Hubacek, Zdenek
System: The UNT Digital Library
Finding the Higgs boson of the standard model in the channel ZH → e<sup>+</sup>e<sup>-</sup>b$\bar{b}$ with the D0 detector at the Tevatron; Recherche du boson de Higgs du nideke standard dans le canal ZH → e<sup>+</sup>e<sup>-</sup>b$\bar{b}$ Avec le Detecteur DØ Aupres du Tevatron (open access)

Finding the Higgs boson of the standard model in the channel ZH → e<sup>+</sup>e<sup>-</sup>b$\bar{b}$ with the D0 detector at the Tevatron; Recherche du boson de Higgs du nideke standard dans le canal ZH → e<sup>+</sup>e<sup>-</sup>b$\bar{b}$ Avec le Detecteur DØ Aupres du Tevatron

The organization of this thesis consists of three main ideas: the first presents the theoretical framework and experimental, as well as objects used in the analysis and the second relates to the various work tasks of service that I performed on the calorimeter, and the third is the search for the Higgs boson in the channel ZH → e<sup>+</sup>e<sup>-</sup>b$\bar{b}$. Thus, this thesis has the following structure: Chapter 1 is an introduction to the standard model of particle physics and the Higgs mechanism; Chapter 2 is an overview of the complex and the acceleration of the Tevatron at Fermilab DØ detector; Chapter 3 is an introduction to physical objects used in this thesis; Chapter 4 presents the study made on correcting the energy measured in the calorimeter; Chapter 5 describes the study of certification of electrons in the calorimeter; Chapter 6 describes the study of certification of electrons in the intercryostat region of calorimeter; Chapter 7 Detailed analysis on the search for Higgs production in the channel ZH → e<sup>+</sup>e<sup>-</sup>b$\bar{b}$; and Chapter 8 presents the final results of the calculations of upper limits to the production cross section of the Higgs boson on a range of low masses.
Date: June 11, 2010
Creator: Calpas, Betty Constante
System: The UNT Digital Library
Measurement of Single Spin Asymmetries in Semi-Inclusive Deep Inelastic Scattering Reaction n↑ ( e,e' pi{sup +}) X at Jefferson Lab (open access)

Measurement of Single Spin Asymmetries in Semi-Inclusive Deep Inelastic Scattering Reaction n↑ ( e,e' pi{sup +}) X at Jefferson Lab

What constitutes the spin of the nucleon? The answer to this question is still not completely understood. Although we know the longitudinal quark spin content very well, the data on the transverse quark spin content of the nucleon is still very sparse. Semi-inclusive Deep Inelastic Scattering (SIDIS) using transversely polarized targets provide crucial information on this aspect. The data that is currently available was taken with proton and deuteron targets. The E06-010 experiment was performed at Jefferson Lab in Hall-A to measure the single spin asymmetries in the SIDIS reaction n↑(e, e′π{sup ±}/K{sup ±})X using transversely polarized {sup 3}He target. The experiment used the continuous electron beam provided by the CEBAF accelerator with a beam energy of 5.9 GeV. Hadrons were detected in a high-resolution spectrometer in coincidence with the scattered electrons detected by the BigBite spectrometer. The kinematic coverage focuses on the valence quark region, x = 0.19 to 0.34, at Q{sup 2} = 1.77 to 2.73 (GeV/c){sup 2}. This is the first measurement on a neutron target. The data from this experiment, when combined with the world data on the proton and the deuteron, will provide constraints on the transversity and Sivers distribution functions on both the u …
Date: June 1, 2010
Creator: Allada, Kalyan
System: The UNT Digital Library
A Study of the Rare Charmless Hadronic B Decay B \to a0 + pi0 Using the BaBar Detector (open access)

A Study of the Rare Charmless Hadronic B Decay B \to a0 + pi0 Using the BaBar Detector

None
Date: June 11, 2013
Creator: Panduro-Vazquez, William
System: The UNT Digital Library
Controlling atomistic processes on Pb films via quantum size effects and lattice rotation (open access)

Controlling atomistic processes on Pb films via quantum size effects and lattice rotation

The two main techniques used to record the data in this dissertation were Spot Profile Analysis - Low Energy Electron Diffraction (SPA-LEED) and Scanning Tunneling Microscopy (STM). A specific data analysis technique for LEED data called G(S) curves is described in depth. G(S) curves can provide a great deal of structural information about the surface; including step heights, island size, and island separation. The effects of quantum size effects (QSE) on the diffusion and critical island sizes of Pb and In on Pb #12;films are reported. Pb depositions on the 2D In phases {radical}3 and {radical}31 to see how the phases affect the Pb growth and its strong QSE are reported.
Date: June 14, 2012
Creator: Binz, Steven
System: The UNT Digital Library
Electroproduction DE Pions Neutres Dans Le Hall a AU Jefferson Laboratory (open access)

Electroproduction DE Pions Neutres Dans Le Hall a AU Jefferson Laboratory

The past decade has seen a strong evolution of the study of the hadron structure through exclusive processes, allowing to access to a more complete description of this structure. Exclusive processes include DVCS (Deeply Virtual Compton Scattering) as well as hard exclusive meson production. This document is particularly focussed on the latter, and more particularly on exclusive neutral pion production. In this thesis is described the analysis of triple coincidence events H(e, e'{gamma}{gamma})X, which were a consequent by-product of the DVCS experiment which occured during Fall 2004 at Jefferson Lab Hall A, to extract the ep {yields} ep{pi}{sup 0} cross section. This cross section has been measured at two values of four-momentum transfer Q{sup 2} = 1.9 GeV{sup 2} and Q{sup 2} = 2.3 GeV{sup 2}. The statistical precision for these measurements is achieved at better than 5 %. The kinematic range allows to study the evolution of the extracted cross section as a function of Q{sup 2} and W. Results are be confronted with Regge inspired calculations and Generalized (GPD) predictions. An intepretation of our data within the framework of semi-inclusive deep inelastic scattering is also discussed.
Date: June 1, 2010
Creator: Fuchey, Eric
System: The UNT Digital Library