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open access

TRISO Fuel Performance: Modeling, Integration into Mainstream Design Studies, and Application to a Thorium-fueled Fusion-Fission Hybrid Blanket

Description: This study focused on creating a new tristructural isotropic (TRISO) coated particle fuel performance model and demonstrating the integration of this model into an existing system of neutronics and heat transfer codes, creating a user-friendly option for including fuel performance analysis within system design optimization and system-level trade-off studies. The end product enables both a deeper understanding and better overall system performance of nuclear energy systems limited or greatly imp… more
Date: November 28, 2011
Creator: Powers, J J
Partner: UNT Libraries Government Documents Department
open access

Target Visualization at the National Ignition Facility

Description: As the National Ignition Facility continues its campaign to achieve ignition, new methods and tools will be required to measure the quality of the targets used to achieve this goal. Techniques have been developed to measure target surface features using a phase-shifting diffraction interferometer and Leica Microsystems confocal microscope. Using these techniques we are able to produce a detailed view of the shell surface, which in turn allows us to refine target manufacturing and cleaning proce… more
Date: November 21, 2011
Creator: Potter, D
Partner: UNT Libraries Government Documents Department
open access

A measurement of neutrino oscillations with muon neutrinos in the MINOS experiment

Description: Experimental evidence has established that neutrino flavor states evolve over time. A neutrino of a particular flavor that travels some distance can be detected in a different neutrino flavor state. The Main Injector Neutrino Oscillation Search (MINOS) is a long-baseline experiment that is designed to study this phenomenon, called neutrino oscillations. MINOS is based at Fermilab near Chicago, IL, and consists of two detectors: the Near Detector located at Fermilab, and the Far Detector, which … more
Date: January 1, 2011
Creator: Coleman, Stephen James & Coll., /William-Mary
Partner: UNT Libraries Government Documents Department
open access

Suppressed Charmed B Decay

Description: This thesis describes the measurement of the branching fractions of the suppressed charmed B{sup 0} {yields} D{sup (*)-} a{sub 0}{sup +} decays and the non-resonant B{sup 0} {yields} D{sup (*)-} {eta}{pi}{sup +} decays in approximately 230 million {Upsilon}(4S) {yields} B{bar B} events. The data have been collected with the BABAR detector at the PEP-II B factory at the Stanford Linear Accelerator Center in California. Theoretical predictions of the branching fraction of the B{sup 0} {yields} D{… more
Date: November 28, 2011
Creator: Snoek, Hella Leonie & /Vrije U., Amsterdam
Partner: UNT Libraries Government Documents Department
open access

Studies of the structure and function of Mms6, a bacterial protein that promotes the formation of magnetic nanoparticles

Description: Here we report structural and functional studies of Mms6, a biomineralization protein that can promote the formation in vitro of magnetic nanoparticles with sizes and morphologies similar to the magnetites synthesized by magnetotactic bacteria. We found the binding pattern of Mms6 to ferric ion to be two-phase and multivalent. We quantatively determined that Mms6 binds one Fe{sup 3+} with a very high affinity (K{sub d} = 10{sup -16} M). The second phase of iron binding is multivalent and cooper… more
Date: May 15, 2011
Creator: Wang, Lijun
Partner: UNT Libraries Government Documents Department
open access

Mesoporous silica nanoparticles as smart and safe devices for regulating blood biomolecule levels

Description: Stimuli-responsive end-capped MSN materials are promising drug carriers that securely deliver a large payload of drug molecules without degradation or premature release. A general review of the recent progress in this field is presented, including a summary of a series of hard and soft caps for drug encapsulation and a variety of internal and external stimuli for controlled release of different therapeutics, a discussion of the biocompatibility of MSN both in vitro and in vivo, and a descriptio… more
Date: May 15, 2011
Creator: Zhao, Yan
Partner: UNT Libraries Government Documents Department
open access

Search for heavy metastable particles decaying to quark pairs at CDF

Description: We report on the search for heavy metastable particles that decay into quark pairs with a macroscopic lifetime (c{tau} {approx} 1 cm) using data taken with the CDF II detector at Fermilab. We use a data driven background approach, where they build probability density functions to model Standard Model secondary vertices from known processes in order to estimate the background contribution from the Standard Model. No statistically significant excess is observed above the background. Limits on the… more
Date: March 1, 2011
Creator: Kwang, Shawn Andrew
Partner: UNT Libraries Government Documents Department
open access

Study of the production of the sigma b*+- with the CDF detector at the Tevatron

Description: The composition of matter is a topic in which the man has been interested throughout History. Since the introduction of the atom by Democritus in the 5th century BC until the establishment of the Standard Model, our successful theory that contains our current knowledge on the matter and their interactions, it has come a long way trying to solve this fundamental question. The efforts of many of the greatest minds to perform crucial experiments and develop theoretical models have helped to get de… more
Date: February 1, 2011
Creator: Calancha Paredes, Constantino & /Madrid, CIEMAT /Madrid U.
Partner: UNT Libraries Government Documents Department
open access

Organic Light-Emitting Diodes (OLEDs) and Optically-Detected Magnetic Resonance (ODMR) studies on organic materials

Description: Organic semiconductors have evolved rapidly over the last decades and currently are considered as the next-generation technology for many applications, such as organic light-emitting diodes (OLEDs) in flat-panel displays (FPDs) and solid state lighting (SSL), and organic solar cells (OSCs) in clean renewable energy. This dissertation focuses mainly on OLEDs. Although the commercialization of the OLED technology in FPDs is growing and appears to be just around the corner for SSL, there are still… more
Date: November 30, 2011
Creator: Cai, Min
Partner: UNT Libraries Government Documents Department
open access

Search for the Standard Model Higgs Boson in Missing Transverse Energy and $b$-quark Final States Using Proton-Antiproton Collisions at 1.96 TeV

Description: A search for the standard model Higgs boson is performed in 6.4 fb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV, collected with the D0 detector during Run II of the Fermilab Tevatron. The final state considered is a pair of jets originating from b quarks and missing transverse energy, as expected from p{bar p} {yields} ZH {yields} {nu}{bar {nu}}b{bar b} production. The search is also sensitive to the WH {yields} {ell}{nu}b{bar b} channel, where the charged lepton is not identified. B… more
Date: March 1, 2011
Creator: Dorland, Tyler M. & /Washington U., Seattle
Partner: UNT Libraries Government Documents Department
open access

Antineutrino Oscillations in the Atmospheric Sector

Description: This thesis presents measurements of the oscillations of muon antineutrinos in the atmospheric sector, where world knowledge of antineutrino oscillations lags well behind the knowledge of neutrinos, as well as a search for {nu}{sub {mu}} {yields} {bar {nu}}{sub {mu}} transitions. Differences between neutrino and antineutrino oscillations could be a sign of physics beyond the Standard Model, including non-standard matter interactions or the violation of CPT symmetry. These measurements leverage … more
Date: May 1, 2011
Creator: Himmel, Alexander I. & /Caltech
Partner: UNT Libraries Government Documents Department
open access

Measurement of CP Violation in B Anti-B Mixing on the Recoil of Partially Reconstructed Anti-B0 to D* L- Anti-Nu/L Using Kaon Tags

Description: After its formulation in 1960's the Standard Model of Fundamental Interactions has gone through an impressive series of successes, begun with the discovery of neutral weak currents [1] and the experimental observations of the massive carriers of weak interactions, the W{sup {+-}} and Z{sup 0} bosons [2], [3]. High precision measurements performed at LEP and SLAC test the validity of the theory to an unprecedented level of accuracy and do not show any significant deviations with respect to the S… more
Date: November 16, 2011
Creator: Gaz, Alessandro & U., /Padua
Partner: UNT Libraries Government Documents Department
open access

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

Description: 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) {… more
Date: June 22, 2011
Creator: Martinelli, Maurizio & U., /Bari
Partner: UNT Libraries Government Documents Department
open access

Measuring neutrino oscillation parameters using $\nu_\mu$ disappearance in MINOS

Description: MINOS is a long-baseline neutrino oscillation experiment. It consists of two large steel-scintillator tracking calorimeters. The near detector is situated at Fermilab, close to the production point of the NuMI muon-neutrino beam. The far detector is 735 km away, 716m underground in the Soudan mine, Northern Minnesota. The primary purpose of the MINOS experiment is to make precise measurements of the 'atmospheric' neutrino oscillation parameters ({Delta}m{sub atm}{sup 2} and sin{sup 2} 2{theta}{… more
Date: February 1, 2011
Creator: Backhouse, Christopher James
Partner: UNT Libraries Government Documents Department
open access

Forward-Backward Asymmetry at High Mass in $t\bar{t}$ Production in $p\bar{p}$ Collisions at $\sqrt{s} = 1.96$ TeV

Description: Current understanding of particle physics postulates that there are 17 fundamental particles that interact via four fundamental forces - gravity, the strong force, the weak force, and the electromagnetic force. These fundamental particles can be classified by their spins into bosons, which are the force-carrying particles with integer spins, and fermions, which have half-integer spins. Fermions can be further divided into quarks and leptons. The particles and three of the four forces - all but … more
Date: April 1, 2011
Creator: Eppig, Andrew
Partner: UNT Libraries Government Documents Department
open access

Measurement of low $p_{T}$ $D^{0}$ meson production cross section at CDF II.

Description: In this thesis we present a study of the production of D{sup 0} meson in the low transverse momentum region. In particular the inclusive differential production cross section of the D{sup 0} meson (in the two-body decay channel D{sup 0} {yields} K{sup -}{pi}{sup +}) is obtained extending the published CDF II measurement to p{sub T} as low as 1.5 GeV/c. This study is performed at the Tevatron Collider at Fermilab with the CDF II detector.
Date: May 1, 2011
Creator: Mussini, Manuel & U., /Bologna
Partner: UNT Libraries Government Documents Department
open access

Observation of the doubly strange b-Baryon Omega(b)-

Description: This thesis reports the first experimental evidence of the doubly strange b-baryon {Omega}{sub b}{sup -} (ssb) following the decay channel {Omega}{sub b}{sup -} {yields} J/{psi}(1S) {mu}{sup +}{mu}{sup -} {Omega}{sup -} {Lambda} K{sup -} p {pi}{sup -} in p{bar p} collisions at {radical}s = 1.96 Tev. Using approximately 1.3 fb{sup -1} of data collected with the D0 detector at the Fermilab Tevatron Collider, they observe 17.8 {+-} 4.9(stat) {+-} 0.8(syst) {Omega}{sub b}{sup -} signal events at 6.… more
Date: February 1, 2011
Creator: Hernandez Orduna, de Jesus, Jose
Partner: UNT Libraries Government Documents Department
open access

Study of the top quark electric charge at the CDF experiment

Description: We report on the measurement of the top quark electric charge using the jet charge tagging method on events containing a single lepton collected by the CDF II detector at Fermilab between February 2002 and February 2010 at the center-of-mass energy {radical}s = 1.96 TeV. There are three main components to this measurement: determining the charge of the W (using the charge of the lepton), pairing the W with the b-jet to ensure that they are from the same top decay branch and finally determining … more
Date: September 1, 2011
Creator: Bartos, Pavol
Partner: UNT Libraries Government Documents Department
open access

Magnetic spectroscopy and microscopy of functional materials

Description: Heusler intermetallics Mn{sub 2}Y Ga and X{sub 2}MnGa (X; Y =Fe, Co, Ni) undergo tetragonal magnetostructural transitions that can result in half metallicity, magnetic shape memory, or the magnetocaloric effect. Understanding the magnetism and magnetic behavior in functional materials is often the most direct route to being able to optimize current materials for todays applications and to design novel ones for tomorrow. Synchrotron soft x-ray magnetic spectromicroscopy techniques are well suite… more
Date: January 28, 2011
Creator: Jenkins, C.A.
Partner: UNT Libraries Government Documents Department
open access

A measurement of the 2 neutrino double beta decay rate of Te-130 in the CUORICINO experiment

Description: CUORICINO was a cryogenic bolometer experiment designed to search for neutrinoless double beta decay and other rare processes, including double beta decay with two neutrinos (2{nu}{beta}{beta}). The experiment was located at Laboratori Nazionali del Gran Sasso and ran for a period of about 5 years, from 2003 to 2008. The detector consisted of an array of 62 TeO{sub 2} crystals arranged in a tower and operated at a temperature of #24;10 mK. Events depositing energy in the detectors, such as radi… more
Date: November 3, 2011
Creator: Kogler, Laura
Partner: UNT Libraries Government Documents Department
open access

Phase-field investigation on the non-equilibrium interface dynamics of rapid alloy solidification

Description: The research program reported here is focused on critical issues that represent conspicuous gaps in current understanding of rapid solidification, limiting our ability to predict and control microstructural evolution (i.e. morphological dynamics and microsegregation) at high undercooling, where conditions depart significantly from local equilibrium. More specifically, through careful application of phase-field modeling, using appropriate thin-interface and anti-trapping corrections and addressi… more
Date: August 15, 2011
Creator: Choi, Jeong
Partner: UNT Libraries Government Documents Department
open access

Optimization of Operating Parameters for Minimum Mechanical Specific Energy in Drilling

Description: Efficiency in drilling is measured by Mechanical Specific Energy (MSE). MSE is the measure of the amount of energy input required to remove a unit volume of rock, expressed in units of energy input divided by volume removed. It can be expressed mathematically in terms of controllable parameters; Weight on Bit, Torque, Rate of Penetration, and RPM. It is well documented that minimizing MSE by optimizing controllable factors results in maximum Rate of Penetration. Current methods for computing MS… more
Date: May 25, 2011
Creator: Hamrick, Todd
Partner: UNT Libraries Government Documents Department
open access

Measurement of branching fractions of B decays to K1(1270)pi and K1(1400)pi and determination of the CKM angle alpha from B0 --> a1(1260) - pi-

Description: In the Standard Model, CP violation in weak interactions involving quarks is parameterized by an irreducible complex phase in the Cabibbo-Kobayashi-Maskawa (CKM) quark-mixing-matrix. The precise determination of the CKM elements is a necessary ingredient for a stringent test of the Standard Model predictions, and is a crucial input for reducing the theoretical error in many New Physics searches with flavor, e.g., in the kaon sector. The unitarity of the CKM matrix is typically expressed as a tr… more
Date: February 7, 2011
Creator: Stracka, Simone & /SLAC, /Milan U.
Partner: UNT Libraries Government Documents Department
open access

Measurement and Interpretation of Moments of the Combined Hadronic Mass and Energy Spectrum in Inclusive Semileptonic B-Meson Decays

Description: This thesis presents first measurements of moments of the hadronic n{sub X}{sup 2} distribution measured in inclusive semileptonic decays of B mesons to final states containing a charm quark, B {yields} X{sub c}{ell}{nu}. The variable n{sub X}{sup 2} is a combination of the invariant mass of the charmed meson m{sub X}, its energy in the B-meson rest-frame E{sub X;BRF}, and a constant {tilde {Lambda}} = 0.65 GeV, n{sub X}{sup 2} = m{sub X}{sup 2}c{sup 4}-2{tilde {Lambda}}E{sub X,BRF} + {tilde {L… more
Date: August 12, 2011
Creator: Klose, Verena
Partner: UNT Libraries Government Documents Department
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