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Solid State Neutron Detectors

Description: No Description Available.
Date: May 1, 1961
Creator: Murphy, J. F.
Partner: UNT Libraries Government Documents Department
open access

Observation of Disappearance of Muon Neutrinos in the NuMI Beam

Description: The Main Injector Neutrino Oscillation Search (MINOS) is a two detector long-baseline neutrino experiment designed to study the disappearance of muon neutrinos. MINOS will test the {nu}{sub {mu}} {yields} {nu}{sub {tau}} oscillation hypothesis and measure precisely {Delta}m{sub 23}{sup 2} and sin{sup 2} 2{theta}{sub 23} oscillation parameters. The source of neutrinos for MINOS experiment is Fermilab's Neutrinos at the Main Injector (NuMI) beamline. The energy spectrum and the composition of the… more
Date: May 1, 2008
Creator: Pavlovic, Zarko
Partner: UNT Libraries Government Documents Department
open access

Two-photon Photoemission of Organic Semiconductor Molecules on Ag(111)

Description: Angle- and time-resolved two-photon photoemission (2PPE) was used to study systems of organic semiconductors on Ag(111). The 2PPE studies focused on electronic behavior specific to interfaces and ultrathin films. Electron time dynamics and band dispersions were characterized for ultrathin films of a prototypical n-type planar aromatic hydrocarbon, PTCDA, and representatives from a family of p-type oligothiophenes.In PTCDA, electronic behavior was correlated with film morphology and growth modes… more
Date: May 15, 2008
Creator: Yang, Aram & Yang, Aram
Partner: UNT Libraries Government Documents Department
open access

Search for pair production of scalar top quarks in jets and missing transverse energy channel with the D0 detector

Description: This dissertation describes a search for the pair production of scalar top quarks, {tilde t}{sub 1}, using a luminosity of 995 pb{sup -1} of data collected in p{bar p} collisions with the D0 detector at the Fermilab Tevatron Collider at a center-of-mass energy {radical}s = 1.96 TeV. Both scalar top quarks are assumed to decay into a charm quark and a neutralino, {tilde {chi}}{sub 1}{sup 0}, where {tilde {chi}}{sub 1}{sup 0} is the lightest supersymmetric particle. This leads to a final state wi… more
Date: May 1, 2008
Creator: Shamim, Mansoora & U., /Kansas State
Partner: UNT Libraries Government Documents Department
open access

Seismic velocity estimation from time migration

Description: This is concerned with imaging and wave propagation in nonhomogeneous media, and includes a collection of computational techniques, such as level set methods with material transport, Dijkstra-like Hamilton-Jacobi solvers for first arrival Eikonal equations and techniques for data smoothing. The theoretical components include aspects of seismic ray theory, and the results rely on careful comparison with experiment and incorporation as input into large production-style geophysical processing code… more
Date: May 31, 2007
Creator: Cameron, Maria Kourkina
Partner: UNT Libraries Government Documents Department
open access

Search for pair production of second generation scalar leptoquarks in ppbar collisions at the Tevatron

Description: As predicted by numerous extensions of the Standard Model, leptoquarks (LQ) are hypothetical bosons allowing lepton-quark transitions. Under the assumption that they couple only to quarks and leptons of the same generation, three generations of leptoquarks can be distinguished. The search for the pair production of second generation scalar leptoquarks has been carried out in p{bar p} collisions at {radical}s = 1.96TeV, using an integrated luminosity of 1 fb{sup -1} collected by the D0 experimen… more
Date: May 1, 2008
Creator: Calfayan, Philippe
Partner: UNT Libraries Government Documents Department
open access

Nanocrystal Bioassembly: Asymmetry, Proximity, and Enzymatic Manipulation

Description: Research at the interface between biomolecules and inorganic nanocrystals has resulted in a great number of new discoveries. In part this arises from the synergistic duality of the system: biomolecules may act as self-assembly agents for organizing inorganic nanocrystals into functional materials; alternatively, nanocrystals may act as microscopic or spectroscopic labels for elucidating the behavior of complex biomolecular systems. However, success in either of these functions relies heavily up… more
Date: May 1, 2008
Creator: Claridge, Shelley A
Partner: UNT Libraries Government Documents Department
open access

Measurement of the Top Quark Mass at CDF Using the Template Method in the Lepton + Jets Channel

Description: A measurement of the top quark mass in p{bar p} collisions at {radical}s = 1.96 TeV is presented. The analysis uses a template method, in which the overconstrained kinematics of the Lepton+Jets channel of the t{bar t} system are used to measure a single quantity, the reconstructed top quark mass, that is strongly correlated with the true top quark mass. in addition, the dijet mass of the hadronically decaying W boson is used to constrain in situ the uncertain jet energy scale in the CDF detecto… more
Date: May 1, 2008
Creator: Adelman, Jahred A.
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

Probing the Energy Transfer Dynamics of Photosynthetic Reaction Center Complexes Through Hole-Burning and Single-Complex Spectroscopy

Description: Photosynthesis is the process by which light energy is used to drive reactions that generate sugars to supply energy for cellular processes. It is one of the most important fundamental biological reactions and occurs in both prokaryotic (e.g. bacteria) and eukaryotic (e.g. plants and algae) organisms. Photosynthesis is also remarkably intricate, requiring the coordination of many different steps and reactions in order to successfully transform absorbed solar energy into a biochemical usable for… more
Date: May 1, 2008
Creator: Riley, Kerry
Partner: UNT Libraries Government Documents Department
open access

Quantum Dynamical Behaviour in Complex Systems - A Semiclassical Approach

Description: One of the biggest challenges in Chemical Dynamics is describing the behavior of complex systems accurately. Classical MD simulations have evolved to a point where calculations involving thousands of atoms are routinely carried out. Capturing coherence, tunneling and other such quantum effects for these systems, however, has proven considerably harder. Semiclassical methods such as the Initial Value Representation (SC-IVR) provide a practical way to include quantum effects while still utilizing… more
Date: May 22, 2008
Creator: Gliebe, Cheryn E & Ananth, Nandini
Partner: UNT Libraries Government Documents Department
open access

Inclusive Rates and Spectra of the Lambda, Cascade, and Omega Hyperons atBaBar

Description: We employ Runs 1-4 off-peak data sample (about 21.5 fb{sup -1}) to produce the current world-best spectra and production rates measurements for three strangely-flavored baryons: the {Lambda} hyperon, the cascade hyperon, and the {Omega} hyperon. These improved measurements shall enable theoretical and phenomelogical workers to generate more realistic models for the hadronization process, currently one of the unresolved problem areas in the standard model of particle physics. This analysis was c… more
Date: May 19, 2008
Creator: Chien, Andrew L.
Partner: UNT Libraries Government Documents Department
open access

Optimization of accelerator parameters using normal form methods on high-order transfer maps

Description: Methods of analysis of the dynamics of ensembles of charged particles in collider rings are developed. The following problems are posed and solved using normal form transformations and other methods of perturbative nonlinear dynamics: (1) Optimization of the Tevatron dynamics: (a) Skew quadrupole correction of the dynamics of particles in the Tevatron in the presence of the systematic skew quadrupole errors in dipoles; (b) Calculation of the nonlinear tune shift with amplitude based on the resu… more
Date: May 1, 2007
Creator: Snopok, Pavel
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

Measurement of the production rate of the charm jet recoiling against the W boson using the D0 detector at the Fermilab Tevatron Collider

Description: This dissertation describes a measurement of the rate of associated production of the W boson with the charm jet in the proton and anti-proton collisions at the center-of-mass energy of 1.96 TeV at the Fermilab Tevatron Collider. The measurement has direct sensitivity to the strange quark content inside the proton. A direct measurement of the momentum distribution of the strange quark inside the proton is essential for a reliable calculation of new physics signal as well as the background proce… more
Date: May 1, 2008
Creator: Ahsan, Mahsana & U., /Kansas State
Partner: UNT Libraries Government Documents Department
open access

Measurement of top quark mass in the all hadronic channel in s**(1/2) = 1.96 TeF, ppbar collisions at D0

Description: A measurement of the top quark mass in proton-antiproton collisions at {radical}s = 1.96 TeV using 1040fb{sup -1} of data collected in D detector at Fermilab is presented. This analysis focuses on the all-hadronic decay mode of the top quark and therefore only events with six or more calorimeter jets in the final state are considered.
Date: May 1, 2008
Creator: Lam, David Wai Kui & U., /Notre Dame
Partner: UNT Libraries Government Documents Department
open access

Intense Ion Beam for Warm Dense Matter Physics

Description: The Neutralized Drift Compression Experiment (NDCX) at Lawrence Berkeley National Laboratory is exploring the physical limits of compression and focusing of ion beams for heating material to warm dense matter (WDM) and fusion ignition conditions. The NDCX is a beam transport experiment with several components at a scale comparable to an inertial fusion energy driver. The NDCX is an accelerator which consists of a low-emittance ion source, high-current injector, solenoid matching section, induct… more
Date: May 23, 2008
Creator: Coleman, Joshua Eugene
Partner: UNT Libraries Government Documents Department
open access

Model Independent Search For New Physics At The Tevatron

Description: The Standard Model of elementary particles can not be the final theory. There are theoretical reasons to expect the appearance of new physics, possibly at the energy scale of few TeV. Several possible theories of new physics have been proposed, each with unknown probability to be confirmed. Instead of arbitrarily choosing to examine one of those theories, this thesis is about searching for any sign of new physics in a model-independent way. This search is performed at the Collider Detector at F… more
Date: May 1, 2008
Creator: Choudalakis, Georgios
Partner: UNT Libraries Government Documents Department
open access

Odd-Z Transactinide Compound Nucleus Reactions Including the Discovery of 260Bh

Description: Several reactions producing odd-Z transactinide compound nuclei were studiedwith the 88-Inch Cyclotron and the Berkeley Gas-Filled Separator at the LawrenceBerkeley National Laboratory. The goal was to produce the same compound nucleus ator near the same excitation energy with similar values of angular momentum via differentnuclear reactions. In doing so, it can be determined if there is a preference in entrancechannel, because under these experimental conditions the survival portion of Swiatec… more
Date: May 14, 2008
Creator: Nelson, Sarah L & Nelson, Sarah L
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
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