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Ejection of Large Fragments in High-Energy Nuclear Reactions

Description: Several features of the production of Na/sup 24/ and Mg/sup 28/ fragments produced in the interaction of protons and He ions with Cu, Ag, Au, and U were investigated. Formation cross sections were determined for He ions of different energies between 320 and 880 Mev and for protons of 700 Mev. Thick- target recoil experiments were performed at bombarding energies of 0.7 and 3 Bev for protons, and 880 Mev for He ions. Also given are some recoil measurements of Na/sup 24/ from Al. Analysis of data… more
Date: September 1, 1961
Creator: Crespo, V. P.
Partner: UNT Libraries Government Documents Department
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Investigation of the validity of the OZI rule and study of production properties of the anti K*/sup. / resonance in. pi. /sup +/p interactions at 16 GeV/c

Description: Results are reported from a streamer chamber experiment performed at Stanford Linear Accelerator Center (SLAC) to study the production of the phi (1020) in OZI-allowed and forbidden processes in ..pi../sup +/p interactions at 16 GeV/c. Production properties of the anti K*/sup ./(896) are also studied and discussed.
Date: September 1, 1981
Creator: Jawahery, A.
Partner: UNT Libraries Government Documents Department
open access

Search for Higgs Boson Production in Association with the W boson in 1.96-TeV Proton-Antiproton Collisions

Description: A search for the Standard Model Higgs boson was carried out in WH {yields} {ell}{nu}b{bar b} process in p{bar p} collisions at a center of mass energy of 1.96 TeV, where W, H, {ell}, {nu}, b and p denote either a W{sup +} or W{sup -} boson, Higgs boson, lepton (electron or muon), neutrino, bottom quark and proton, respectively. The data were collected with the Collider Detector at Fermilab from February 2002 to August 2004. The corresponding integrated luminosity is 319 pb{sup -1}. We select ev… more
Date: September 1, 2005
Creator: Ishizawa, Yoshio
Partner: UNT Libraries Government Documents Department
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Coupling of the 4f Electrons in Lanthanide Molecules

Description: (C5Me5)2LnOTf where Ln = La, Ce, Sm, Gd, and Yb have been synthesized and these derivatives are good starting materials for the synthesis of (C5Me5)2LnX derivatives. (C5Me5)2Ln(2,2'-bipyridine), where Ln = La, Ce, Sm, and Gd, along with several methylated bipyridine analogues have been synthesized and their magnetic moments have been measured as a function of temperature. In lanthanum, cerium, and gadolinium complexes the bipyridine ligand ligand is unequivocally the radical anion, and the obse… more
Date: September 12, 2008
Creator: Kazhdan, Daniel
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

Measurement of the top quark pair production cross-section in dimuon final states in proton-antiproton collisions at 1.96 TeV

Description: Particle physics deals with the fundamental building blocks of matter and their interactions. The vast number of subatomic particles can be reduced to twelve fundamental fermions, which interact by the exchange of spin-1 particles as described in the Standard Model (SM) of particle physics. The SM provides the best description of the subatomic world to date, despite the fact it does not include gravitation. Following the relation {lambda} = h/p, where h is Planck's constant, for the examination… more
Date: September 1, 2008
Creator: Konrath, Jens Peter
Partner: UNT Libraries Government Documents Department
open access

A Search for Neutrinoless Tau Decays to Three Leptons

Description: Using approximately 350 million {tau}{sup +}{tau}{sup -} pair events recorded with the BaBar detector at the Stanford Linear Accelerator Center between 1999 and 2006, a search has been made for neutrinoless, lepton-flavor violating tau decays to three lighter leptons. All six decay modes consistent with conservation of electric charge and energy have been considered. With signal selection efficiencies of 5-12%, we obtain 90% confidence level upper limits on the branching fraction {Beta}({tau} {… more
Date: September 24, 2008
Creator: Kolb, Jeffrey A. & /SLAC, /Oregon U.
Partner: UNT Libraries Government Documents Department
open access

Study of the Ds+ to K+K-e+ nu Decay Channel with the BaBar Experiment

Description: Charm semileptonic decays allow a validation of lattice QCD calculations through the measurement of the hadronic form factors, which characterize the effect of strong interaction in these reactions. The accuracy of such calculations is crucial for the improvement of the test of the standard model in flavor physics. This thesis presents a study of the D{sub s}{sup +} {yields} K{sup +}K{sup -}e{sup +}{nu}{sub e} channel using 214 fb{sup -1} recorded by de BAbar experiment. For events with a K{sup… more
Date: September 9, 2008
Creator: Serrano, Justine & /Orsay, IPN /SLAC
Partner: UNT Libraries Government Documents Department
open access

Search for B to rho/omega gamma decays at BaBar

Description: The authors present the results of the search for the decays B{sup 0/{+-}} {yields} {rho}{sup 0/{+-}}{gamma} (previously observed) and B{sup 0} {yields} {omega}{gamma} (for which currently only an upper limit exists). Together with B {yields} K*{gamma} decays, B {yields} ({rho}/{omega}){gamma} allow us to measure the ratio of CKM-matrix elements |V{sub td}/V{sub ts}|. The analysis is based on the full BABAR dataset of 424.35 fb{sup -1} corresponding to 465 million B{bar B} pairs, and makes heav… more
Date: September 23, 2008
Creator: Piatenko, Timofei & /SLAC, /Caltech
Partner: UNT Libraries Government Documents Department
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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

A Parallel Ocean Model With Adaptive Mesh Refinement Capability For Global Ocean Prediction

Description: An ocean model with adaptive mesh refinement (AMR) capability is presented for simulating ocean circulation on decade time scales. The model closely resembles the LLNL ocean general circulation model with some components incorporated from other well known ocean models when appropriate. Spatial components are discretized using finite differences on a staggered grid where tracer and pressure variables are defined at cell centers and velocities at cell vertices (B-grid). Horizontal motion is model… more
Date: September 8, 2005
Creator: Herrnstein, A
Partner: UNT Libraries Government Documents Department
open access

Plasma ion sources and ion beam technology inmicrofabrications

Description: For over decades, focused ion beam (FIB) has been playing a very important role in microscale technology and research, among which, semiconductor microfabrication is one of its biggest application area. As the dimensions of IC devices are scaled down, it has shown the need for new ion beam tools and new approaches to the fabrication of small-scale devices. In the meanwhile, nanotechnology has also deeply involved in material science research and bioresearch in recent years. The conventional FIB… more
Date: September 1, 2007
Creator: Ji, Lili
Partner: UNT Libraries Government Documents Department
open access

Measurement of the Top Quark Mass Simultaneously in Dilepton and Lepton + Jets Decay Channels

Description: The authors present the first measurement of the top quark mass using simultaneously data from two decay channels. They use a data sample of {radical}s = 1.96 TeV collisions with integrated luminosity of 1.9 fb{sup -1} collected by the CDF II detector. They select dilepton and lepton + jets channel decays of t{bar t} pairs and reconstruct two observables in each topology. They use non-parametric techniques to derive probability density functions from simulated signal and background samples. The… more
Date: September 1, 2008
Creator: Fedorko, Wojciech T.
Partner: UNT Libraries Government Documents Department
open access

Observation of Bs-Bsbar Oscillations Using Partially Reconstructed Hadronic Bs Decays

Description: This thesis describes the contribution of partially reconstructed hadronic decays in the world's first observation of B{sub s}{sup 0}-{bar B}{sub s}{sup 0} oscillations. The analysis is a core member of a suite of closely related studies whose combined time-dependent measurement of the B{sub s}{sup 0}-{bar B}{sub s}{sup 0} oscillation frequency {Delta}m{sub s} is of historic significance. Using a data sample of 1 fb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV collected with the CDF-… more
Date: September 1, 2007
Creator: Miles, Jeffrey Robert
Partner: UNT Libraries Government Documents Department
open access

Search for Higgs Bosons and Supersymmetric Particles in Tau Final States

Description: Elementary particle physics tries to find an answer to no minor question: What is our universe made of? To our current knowledge, the elementary constituents of matter are quarks and leptons, which interact via four elementary forces: electromagnetism, strong force, weak force and gravity. All forces, except gravity, can be described in one framework, the Standard Model of particle physics. The model's name reflects its exceptional success in describing all available experimental high energy ph… more
Date: September 1, 2008
Creator: Torchiani, Ingo & U, /Freiburg
Partner: UNT Libraries Government Documents Department
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Mesure DE La Section Efficace DE Production DE Paires DE Quarks Top Dans L'Etat Final DI-Electron Avec Les Donnees Collectees Par L'Experience d0 AU Runiia

Description: The top quark has been discovered in 1995 by CDF and D0 collaborations in proton-antiproton collisions at the Tevatron. The amount of data recorded by both experiments makes it possible to accurately measure the properties of this very massive quark. This thesis is devoted to the measurement of the top pair production cross-section via the strong interaction, in a final state composed of two electrons, two particle jets and missing transverse energy. It is based on a 1 fb{sup -1} data set colle… more
Date: September 1, 2008
Creator: Martin Dit Latour, Bertrand & /LPSC, Grenoble
Partner: UNT Libraries Government Documents Department
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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
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Measurement of the top quark pair production cross section in the dilepton channel using lepton+track selection

Description: The production cross section for t{bar t} pairs decaying into two lepton final states was measured using data from the D0 detector at Fermilab. The measurement was made using a lepton+track selection, where one lepton is fully identified and the second lepton is observed as an isolated track. This analysis is designed to complement similar studies using two fully identified leptons [1]. The cross section for the lepton+track selection was found to be {sigma} = 5.2{sub -1.4}{sup +1.6}(stat){sub … more
Date: September 1, 2008
Creator: Wagner, Robert Emil
Partner: UNT Libraries Government Documents Department
open access

Search for supersymmetric partner of bottom quark at d0 at Tevatron. Studies on missing transverse energy

Description: Supersymmetry, extension of the Standard Model of Particle Physics (SM), is searched for by trying to observe the supersymmetric partner of bottom quark ({tilde b}). This search is performed using events with a final state comprising two acoplanar b-quark jets and missing transverse energy (MET) and coming from a sample of 992 pb{sup -1} of data collected by the D0 detector at the Tevatron, the Fermilab p{bar p} collider. The absence of an excess of events in comparison to MS expectations leads… more
Date: September 1, 2007
Creator: Calvet, Samuel Pierre
Partner: UNT Libraries Government Documents Department
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A study of Central Exclusive Production

Description: Central exclusive production of a system X in a collision between two hadrons h is defined as hh {yields} h + X + h with no other activity apart from the decay products of X. This thesis presents predictions for the production cross section of a CP violating supersymmetric Higgs boson and the radion of the Randall-Sundrum model. The ExHuME Monte Carlo generator was written to simulate central exclusive processes and is described and explored. A comparison to di-jet observations made by the D0 d… more
Date: September 1, 2008
Creator: Monk, James
Partner: UNT Libraries Government Documents Department
open access

A Measurement of the Top Quark Mass in 1.96 TeV Proton-Antiproton Collisions Using a Novel Matrix Element Method

Description: A measurement of the top quark mass in t{bar t} {yields} l + jets candidate events, obtained from p{bar p} collisions at {radical}s = 1.96 TeV at the Fermilab Tevatron using the CDF II detector, is presented. The measurement approach is that of a matrix element method. For each candidate event, a two dimensional likelihood is calculated in the top pole mass and a constant scale factor, 'JES', where JES multiplies the input particle jet momenta and is designed to account for the systematic uncer… more
Date: September 30, 2007
Creator: CDF Collaboration
Partner: UNT Libraries Government Documents Department
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