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Cold Fusion Production and Decay of Neutron-Deficient Isotopes of Dubnium and Development of Extraction Systems for Group V Elements

Description: Excitation functions for the 1n and 2n exit channels of the 208Pb(51V,xn)259-xDb reaction were measured. A maximum cross section of the 1n exit channel of 2070+1100/-760 pb was measured at an excitation energy of 16.0 +- 1.8 MeV. For the 2n exit channel, a maximum cross section of 1660+450/-370 pb was measured at 22.0 +- 1.8 MeV excitation energy. The 1n excitation function for the 209Bi(50Ti,n)258Db reaction was remeasured, resulting in a cross section of 5480+1730/1370 pb at an excitation ene… more
Date: July 31, 2008
Creator: Gates, Jacklyn M.
Partner: UNT Libraries Government Documents Department
open access

Measurement of the Inclusive Branching FractionsB(B^- to D^+ Pi^- Pi^-) and B(B^- to D*^+ Pi^- Pi^-)

Description: The D{sub J}{sup 0} is a family of four orbitally excited mesons: D*{sub 2}(2460){sup 0}, D{sub 1}(2420){sup 0}, D{sub 1}(j = 1/2){sup -}, and D*{sub 0}(j = 1/2){sup 0}. This dissertation presents the measurements of the inclusive branching fractions, {Beta}(B{sup -} {yields} D*{sup +}{pi}{sup -}{pi}{sup -}) and {Beta}(B{sup -} {yields} D{sup +}{pi}{sup -}{pi}{sup -}). The D{sub J}{sup 0} provides an intermediate resonance for those two modes. The data used for this analysis consists of Runs 1-… more
Date: July 17, 2007
Creator: Eschenburg, Vance Onno & U., /Mississippi
Partner: UNT Libraries Government Documents Department
open access

Simulating the Growth of a Disk Galaxy and its Supermassive Black Hole in a Cosmological Simulating the Growth of a Disk Galaxy and its Supermassive Black Hole in a Cosmological Context

Description: Supermassive black holes (SMBHs) are ubiquitous in the centers of galaxies. Their formation and subsequent evolution is inextricably linked to that of their host galaxies, and the study of galaxy formation is incomplete without the inclusion of SMBHs. The present work seeks to understand the growth and evolution of SMBHs through their interaction with the host galaxy and its environment. In the first part of the thesis (Chap. 2 and 3), we combine a simple semi-analytic model of outflows from ac… more
Date: July 1, 2008
Creator: Levine, Robyn Deborah & /JILA, Boulder
Partner: UNT Libraries Government Documents Department
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Time Dependent CP Asymmetries and Branching RatioMeasurements in Charmless Three Body B Decays at BABAR

Description: In this work we presented measurements of CP violation and decay rates of B decays in final states not involving a charm quark in the final state. In particular, the time-dependent CP asymmetries of decays which proceed through b {yields} s elementary transition is a particularly sensitive probe of physics beyond the Standard Model. In fact, even if the precise measurements of CP conserving and CP violating processes show the success of the CKM picture of the flavour physics, the sector of b {y… more
Date: July 17, 2007
Creator: Di Marco, Emanuele & U., /Rome
Partner: UNT Libraries Government Documents Department
open access

Diffractive Z/gamma* --> mu+mu- boson production in proton - antiproton collisions

Description: Measurements of the inclusive diffractive Z {yields} {mu}{sup +}{mu}{sup -} cross section with gap requirement for M{sub {mu}}{sub {mu}} > 40 GeV at {radical} s = 1.96 TeV and fraction of Z bosons produced diffractively with gap requirement from Z inclusive production are presented. The measurements are performed using a data sample corresponding to an integrated luminosity of 820 pb{sup -1}, collected with the D0 detector at the Tevatron, between 2002 to 2005. A total of 39945 di-muons even… more
Date: July 1, 2007
Creator: Mendoza Navas, Luis Miguel
Partner: UNT Libraries Government Documents Department
open access

Limit on the muon neutrino magnetic moment and a measurement of the CCPIP to CCQE cross section ratio

Description: A search for the muon neutrino magnetic moment was conducted using the Mini-BooNE low energy neutrino data. The analysis was performed by analyzing the elastic scattering interactions of muon neutrinos on electrons. The analysis looked for an excess of elastic scattering events above the Standard Model prediction from which a limit on the neutrino magnetic could be set. In this thesis, we report an excess of 15.3 {+-} 6.6(stat){+-}4.1(syst) {nu}{sub {mu}e} events above the expected background. … more
Date: July 1, 2008
Creator: Ouedraogo, Serge Aristide & U., /Louisiana State
Partner: UNT Libraries Government Documents Department
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A measurement of the lambda_b lifetime at the D0 experiment

Description: This thesis describes a measurement of the lifetime of the {Lambda}{sub b}{sup 0} baryon, performed using data from proton-antiproton collisions at a centre of mass energy of 1.96 TeV. The decay {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{sup +}{mu}{sup -}{ovr P{nu}}{sub {mu}}X was reconstructed in approximately 1.3 fb{sup -1} of data recorded by the D0 detector in 2002-2006 during Run II of the Fermilab Tevatron collider. A signal of 4437 {+-} 329 {Lambda}{sub c}{sup +}{mu}{sup -} pairs wa… more
Date: July 1, 2007
Creator: Lewin, Marcus Philip
Partner: UNT Libraries Government Documents Department
open access

Dalitz Analysis of D0 to K0(S) Pi+ Pi- and Measurement of the CKM Angle Gamma in Charged B+- Decays to D(*) K+- Decays

Description: Despite more than thirty years having elapsed since the discovery of CP violation, our understanding about the source and the nature of this phenomenon is still very limited. In the standard model of particle physics, CP violation is due to the presence of an non-irreducible weak phase in the Cabibbo-Kabayashi-Maskawa(CKM) matrix. Up to now, all the experimental results are in good agreement with the standard model. However, it is important for us to over-constrain the CKM quark-mixing matrix a… more
Date: July 10, 2007
Creator: Lau, Yan-Pan
Partner: UNT Libraries Government Documents Department
open access

Measurement of the inclusive jet cross section in proton-antiproton collisions at the center-of-mass energy of 1.96 TeV

Description: This thesis studies the high-energy collisions of protons and antiprotons. The data used in the measurement were collected during 2004-2005 with the D0 detector at the Tevatron Collider of the Fermi National Accelerator Laboratory and correspond to 0.7 fb{sup -1} of integrated luminosity. High energy hadron collisions usually produce collimated sprays of particles called jets. The energy of the jets is measured using a liquid Argon-Uranium calorimeter and the production angle is determined with… more
Date: July 1, 2008
Creator: Voutilainen, Mikko Antero & /Saclay, /Helsinki Inst. of Phys. /Helsinki U. of Tech. /Nebraska U.
Partner: UNT Libraries Government Documents Department
open access

Measurement of Pi-K Ratios from the NuMI Target

Description: Interactions of protons (p) with the NuMI (Neutrinos at the Main Injector) target are used to create the neutrino beam for the MINOS (Main Injector Neutrino Oscillation Search) Experiment. Using the MIPP (Main Injector Particle Production) experimental apparatus, the production of charged pions and kaons in p+NuMI interactions is studied. The data come from a sample of 2 x 10{sup 6} events obtained by MIPP using the 120 GeV/c proton beam from the Main Injector at Fermi National Accelerator Labo… more
Date: July 1, 2007
Creator: Seun, Sin Man & U., /Harvard
Partner: UNT Libraries Government Documents Department
open access

A Search for the Production of Technicolor Particles at the D-Zero Detector

Description: A search for the Technicolor processes p{bar p} {yields} {rho}{sub T}{sup {+-}} {yields} W{sup {+-}}{pi}{sub T}{sup 0} {yields} {mu}{nu}b{bar b} and p{bar p} {yields} {rho}{sub T}{sup 0} {yields} W{sup {+-}}{pi}{sub T}{sup {+-}} {yields} {mu}{nu}b{bar c} is conducted at the D0 detector. Selection requirements are individually optimized for each of twenty mass hypotheses by means of a random grid search. No excess is seen in a 291 pb{sup -1} data set and 95% confidence level upper limits are set… more
Date: July 1, 2006
Creator: Desai, Satish Vijay
Partner: UNT Libraries Government Documents Department
open access

Search for the Rare Decay B to pi l+l- in the BaBar Experiment

Description: The rare decay B {yields} {pi}{ell}{sup +}{ell}{sup -} is the simplest manifestation of a b {yields} d{ell}{sup +}{ell}{sup -} flavor-changing neutral current (FCNC) process. This type of process only proceeds through penguin loop or box diagrams and is sensitive to physics at the electroweak scale. It can be used to constrain parameters of the Standard Model and its extensions. B {yields} {pi}{ell}{sup +}{ell}{sup -} events have not yet been observed; the branching fraction is expected to be a… more
Date: July 17, 2007
Creator: Ofte, Ingrid
Partner: UNT Libraries Government Documents Department
open access

Measurement of sigma(p anti-p -> t anti-t) in the tau + jets channel by the D� experiment at Run II of the Tevatron Collider

Description: The top quark is the heaviest and most mysterious of the known elementary particles. Therefore, careful study of its production rate and other properties is of utmost importance for modern particle physics. The Tevatron is the only facility currently capable of studying top quark properties by on-shell production. Measurement of the top quark pair production cross section is one of the major goals of the Tevatron Run II physics program. It provides an excellent test of QCD at energies exceeding… more
Date: July 1, 2008
Creator: Arov, Mikhail
Partner: UNT Libraries Government Documents Department
open access

Search for the Higgs Boson in the ZH->vvbb Channel at CDF Run II

Description: This analysis focuses on a low mass Higgs boson search with 1.7 fb{sup -1} of data. The focus is on Higgs events in which it is produced in association with a W or Z boson. Such events are expected to leave a distinct signature of large missing transverse energy for either a Z {yields} {nu}{nu} decay or a leptonic W decay in which the lepton goes undetected, as well as jets with taggable secondary vertices from the H {yields} b{bar B} decay. Utilizing a new track based technique for removing QC… more
Date: July 1, 2008
Creator: Parks, Brandon Scott
Partner: UNT Libraries Government Documents Department
open access

Rare decays of B mesons and baryons at the Tevatron and the LHC

Description: The experimental study of rare decays of hadrons containing the b quark has been a fertile ground for some time, and keeps being one of the most interesting subjects in high energy physics. It has improved our understanding of hadronic processes, and allows investigating various aspects of the Standard Model and searching for hints of physics beyond the Standard Model. Examples are the comparison of branching fractions of charmless modes with predictions of models, the constraints on CKM angles… more
Date: July 1, 2008
Creator: Volpi, Guido & /INFN, Pisa /Siena U.
Partner: UNT Libraries Government Documents Department
open access

Measurement of CKM-angle gamma with Charmed B0 Meson Decays

Description: This thesis reports measurements of the time-dependent CP asymmetries in fully reconstructed B{sup 0} {yields} (D{sup (*){-+}} and B{sup 0} {yields} D{sup {-+}} {rho}{sup {+-}}) decays in approximately 232 million {Upsilon}(4S) {yields} B{bar B} events, collected with the BABAR detector at the PEP-II asymmetric-energy B factory at the Stanford Linear Accelerator Center in California, as published in Ref. [14]. The phenomenon of CP violation allows one to distinguish between matter and antimatte… more
Date: July 17, 2007
Creator: Baak, Max Arjen & /Vrije U., Amsterdam
Partner: UNT Libraries Government Documents Department
open access

Mesure DU Rapport D'Embranchement ET DU Facteur Deforme DE La D_Sint_Gration b0 to Pilnu, ET D_Termination DE |Vub| Avec Unetechnique DE Reconstruction Rel_Ch_E DU Neutrinoac

Description: The authors report the results of a study of the exclusive charmless semileptonic decay, B{sup 0} {yields} {pi}{sup -}{ell}{sup +}{nu}, undertaken with approximately 227 million B{bar B} pairs collected at the {Upsilon}(4S) resonance with the BABAR detector. The analysis uses events in which the signal B decays are reconstructed with an innovative loose neutrino reconstruction technique. They obtain partial branching fractions in 12 bins of q{sup 2}, the momentum transfer squared, from which th… more
Date: July 17, 2007
Creator: Cote, David & U., /Montreal
Partner: UNT Libraries Government Documents Department
open access

Calibration of new flavor tagging algorithms using Bs oscillations

Description: Over the past decades the current theoretical description, the Standard Model of elementary particle physics, was solidified by many measurements as the basic theory describing fundamental particles and their interactions. It is extremely successful in explaining the high-precision data collected by experiments so far. The Standard Model includes several intrinsic parameters which have to be measured in experiments. Independent analyses of different physical processes can constrain those parame… more
Date: July 1, 2007
Creator: Mack, Philipp
Partner: UNT Libraries Government Documents Department
open access

Search for Excited or Exotic Electron Production Using the Dielectron + Photon Signature at CDF in Run II

Description: The author presents a search for excited or exotic electrons decaying to an electron and a photon with high transverse momentum. An oppositely charged electron is produced in association with the excited electron, yielding a final state dielectron + photon signature. The discovery of excited electrons would be a first indication of lepton compositeness. They use {approx} 202 pb{sup -1} of data collected in p{bar p} collisions at {radical}s = 1.96 TeV with the Collider Detector at Fermilab durin… more
Date: July 1, 2004
Creator: Gerberich, Heather Kay & U., /Duke
Partner: UNT Libraries Government Documents Department
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Implementation of an iterative matching scheme for the Kapchinskij-Vladimirskij equations in the WARP code

Description: The WARP code is a robust electrostatic particle-in-cell simulation package used to model charged particle beams with strong space-charge forces. A fundamental operation associated with seeding detailed simulations of a beam transport channel is to generate initial conditions where the beam distribution is matched to the structure of a periodic focusing lattice. This is done by solving for periodic, matched solutions to a coupled set of ODEs called the Kapchinskij-Vladimirskij (KV) envelope equ… more
Date: July 1, 2008
Creator: Chilton, Sven & Chilton, Sven H.
Partner: UNT Libraries Government Documents Department
open access

Measurements of Branching Fraction and CP Violation inB Meson Rare Decays to Final States containing eta or eta' Mesons in the BaBar Experiment at SLAC

Description: Note that the main goal of this thesis work is the measurement of the branching fractions, charge asymmetry, and Time-Dependent CP Violation in {eta}'K{sup 0} mode. All other measurements are reported here for completion because they are connected by similar physics arguments. They are part of the Milan analysis activity, done by undergraduate students. They should not be considered as done in this thesis work. The measurements of the two body-modes {eta}{eta}, {eta}{phi}, and {eta}'{phi} are u… more
Date: July 17, 2007
Creator: Lazzaro, Alfio & U., /Milan
Partner: UNT Libraries Government Documents Department
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