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Introduction to conformal field theory and string theory

Description: These lectures are meant to provide a brief introduction to conformal field theory (CFT) and string theory for those with no prior exposure to the subjects. There are many excellent reviews already available, and most of these go in to much more detail than I will be able to here. 52 refs., 11 figs.
Date: December 1, 1989
Creator: Dixon, L.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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High energy behavior of fermion--meson and meson--meson scattering in a supersymmetric field theory

Description: A review of the general methods of high energy calculations within the framework of field theory is given. These include Feynman parameter methods, the infinite momentum frame, and Mellin transform methods. A general discussion of supersymmetry is also presented. The basic aspects of the Wess-Zumino model are given. This includes a proof of renormalizability through one-loop, and a derivation of the Feynman rules. The general supersymmetry algebra is presented. The method of generating represen… more
Date: December 1, 1977
Creator: Opoien, J.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Model tests of OTEC-1: test of HMB with and without cold water pipes

Description: In early 1977, ERDA began an extensive study of various factors which could effect the early design and deployment of OTEC-1, a test platform for evaluation of one megawatt (1 MW) OTEC heat exchangers. The platform was to consist of the Hughes Mining Barge (HMB) and a 3000 foot deep cold water pipe (CWP). One of the factors to be considered was the motions of the HMB and the motions, loads and stresses of the CWP. Several theoretical methods, including one developed at HYDRONAUTICS, Incorporate… more
Date: December 1, 1977
Creator: Sheldon, L. R.; Barr, R. A. & O'Dea, J. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Non-Standard Physics in Leptonic and Semileptonic Decays of Charmed Mesons

Description: Recent measurements of the branching fraction for D{sub s} {yields} {ell}v disagree with the Standard Model expectation, which relies on calculations of f{sub D{sub s}} from lattice QCD. This paper uses recent preliminary measurements from CLEO and a new preliminary lattice-QCD result from this conference to update the significance of the discrepancy. The 'f{sub D{sub s}} puzzle' stands now at 3.5{sigma}, with {sigma} predominantly from the statistical uncertainty of the experiments. New physic… more
Date: December 1, 2008
Creator: Kronfeld, Andreas S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Accuracy of Analog Fiber-Optic Links in Pulsed Radiation Environments

Description: Interferometric fiber-optic links used in pulsed-power experiments are evaluated for accuracy in the presence of radiation fields which alter fiber transmission. Amplitude-modulated format (e.g., Mach-Zehnder) and phase-modulated formats are compared. Historically, studies of radiation effects on optical fibers have focused on degradation and recovery of the fibers transmission properties; such work is either in the context of survivability of fibers in catastrophic conditions or suitability of… more
Date: December 1, 2007
Creator: E. K. Miller, G. S. Macrum, I. J. McKenna, et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Global paths of time-periodic solutions of the Benjamin-Ono equation connecting arbitrary traveling waves

Description: We classify all bifurcations from traveling waves to non-trivial time-periodic solutions of the Benjamin-Ono equation that are predicted by linearization. We use a spectrally accurate numerical continuation method to study several paths of non-trivial solutions beyond the realm of linear theory. These paths are found to either re-connect with a different traveling wave or to blow up. In the latter case, as the bifurcation parameter approaches a critical value, the amplitude of the initial condi… more
Date: December 11, 2008
Creator: Ambrose, David M. & Wilkening, Jon
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Local Two-Photon Couplings and the J=0 Fixed Pole in Real and Virtual Compton Scattering

Description: The local coupling of two photons to the fundamental quark currents of a hadron gives an energy-independent contribution to the Compton amplitude proportional to the charge squared of the struck quark, a contribution which has no analog in hadron scattering reactions. We show that this local contribution has a real phase and is universal, giving the same contribution for real or virtual Compton scattering for any photon virtuality and skewness at fixed momentum transfer squared t. The t-depende… more
Date: December 5, 2008
Creator: Brodsky, Stanley J.; Llanes-Estrada, Felipe J. & Szczepaniak, Adam P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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KPiX, An Array of Self Triggered Charge Sensitive Cells Generating Digital Time and Amplitude Information

Description: The Silicon Detector proposed for the International Linear Collider (ILC) requires electronic read-out that can be tightly coupled to the silicon detectors envisioned for the tracker and the electromagnetic calorimeter. The KPiX is a 1024-channel read-out chip that bump-bonds to the detector and communicates through a few digital signals, power, and detector bias. The KPiX front-end is a low-noise dual-range charge-amplifier with a dynamic range of 17 bit, achieved by autonomous switching of th… more
Date: December 11, 2008
Creator: Freytag, D.; Herbst, R.; /SLAC; Brau, J.; U., /Oregon; Breidenbach, M. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Light-Front Holography and Novel Effects in QCD

Description: The correspondence between theories in anti-de Sitter space and conformal field theories in physical space-time leads to an analytic, semiclassical model for strongly-coupled QCD. Light-front holography allows hadronic amplitudes in the AdS fifth dimension to be mapped to frame-independent light-front wavefunctions of hadrons in physical space-time, thus providing a relativistic description of hadrons at the amplitude level. We identify the AdS coordinate z with an invariant light-front coordin… more
Date: December 18, 2008
Creator: Brodsky, Stanley J. & de Teramond, Guy F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Magnetohydrodynamic Simulations of Disk GalaxyFormation: the Magnetization of The Cold and Warm Medium

Description: Using magnetohydrodynamic (MHD) adaptive mesh refinement simulations, we study the formation and early evolution of disk galaxies with a magnetized interstellar medium. For a 10{sup 10} M{sub {circle_dot}} halo with initial NFW dark matter and gas profiles, we impose a uniform 10{sup -9} G magnetic field and follow its collapse, disk formation and evolution up to 1 Gyr. Comparing to a purely hydrodynamic simulation with the same initial condition, we find that a protogalactic field of this stre… more
Date: December 18, 2007
Creator: Wang, Peng; Abel, Tom & /KIPAC, Menlo Park /Santa Barbara, KITP
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Physical limits for high ion charge states in pulsed discharges in vacuum

Description: Short-pulse, high-current discharges in vacuum were investigated with the goal to maximize the ion charge state number. In a direct extension of previous work [Appl. Phys. Lett. 92, 041502 (2008)], the role of pulse length, rate of current rise, and current amplitude was studied. For all experimental conditions, the usable (extractable) mean ion charge state could not be pushed beyond 7+. Instead, a maximum of the mean ion charge state (about 6+ to 7+ for most cathode materials) was found for a… more
Date: December 23, 2008
Creator: Yushkov, Georgy & Anders, Andre
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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HIGH-ENERGY-PHYSICS EXPERIMENTS WITH POLARIZED TARGETS

Description: If we are to do a workmanlike job of studying the strong interactions it is imperative that we have knowledge of the spin dependence of the forces. This implies that polarization experiments are essential. Already Bareyre, Bricman, Stirling and Villet have shown that pion-proton polarization experiments should be interpreted as indicating two new resonances not previously seen by other methods. The present-day approach to determining detailed pion-proton scattering amplitudes is to use measured… more
Date: December 1, 1966
Creator: Chamberlain, Owen
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Limitations and Failures of the Layzer Model

Description: We report several limitations and failure modes of the recently expanded Layzer model for hydrodynamic instabilities. The failures occur for large initial amplitudes, for stable accelerations, and for spikes in two-fluid systems.
Date: December 21, 2007
Creator: Mikaelian, K O
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Physics of reshock and mixing in single-mode Richtmyer-Meshkov instability

Description: The ninth-order weighted essentially non-oscillatory (WENO) shock-capturing method is used to investigate the physics of reshock and mixing in two-dimensional single-mode Richtmyer-Meshkov instability to late times. The initial conditions and computational domain were adapted from the Mach 1.21 air(acetone)/SF{sub 6} shock tube experiment of Collins and Jacobs [J. Fluid Mech. 464, 113 (2002)]: the growth of the bubble and spike perturbation amplitudes from fifth- and ninth-order WENO simulation… more
Date: December 13, 2006
Creator: Schilling, O; Latini, M & Don, W
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Measurement of CP-Violating Asymmetries In Neutral B Meson Decays Into Three Kaons

Description: The Standard Model (SM) of particle physics successfully describes all of the observed interactions of the fundamental particles (with the exception of non-zero neutrino mass). Despite this enormous success, the SM is widely viewed as an incomplete theory. For example, the size of the asymmetry between matter and antimatter is not nearly large enough to account for the abundance of matter observed throughout the universe. It is thus believed that as-yet-unknown physical phenomena must exist tha… more
Date: December 1, 2008
Creator: Thompson, Joshua M.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Is there a hard gluonic contribution to the first moment of g sub 1

Description: We show that the size of the hard gluonic contribution to the first moment of the proton's spin-dependent structure function g{sub 1} is entirely a matter of the convention used in defining the quark distributions. If the UV regulator for the spin-dependent quark distributions respects the gauge invariance of Green's functions (allows shifts of loop momenta) and respects the analyticity structure of the unregulated distributions, then the hard gluonic contribution to the first moment of g{sub 1… more
Date: December 19, 1990
Creator: Bodwin, G.T. (Argonne National Lab., IL (USA)) & Qiu, Jianwei (State Univ. of New York, Stony Brook, NY (USA). Inst. for Theoretical Physics)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Diffusive transport enhancement by isolated resonances and distribution tails growth in hadronic beams

Description: The escape rates and evolution of a distribution of particles are considered for a 2-D model of transverse motion of particles in hadronic storage rings, when nonlinear resonances and external diffusion are present. Dynamic enhancement of diffusion inside separatrices can develop under a certain geometry of resonance oscillations and relatively wide resonances, leading to the fast growth of distribution tails and escape rates. The phenomenon is absent in 1-D. 10 refs., 4 figs.
Date: December 6, 1990
Creator: Gerasimov, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Nuclear decay studies far-from-stability

Description: Nuclear decay studies far-from-stability are performed not merely to characterize new isotopes, but to establish an experimental footing for improving our theoretical understanding of nuclear structure and decay. Although progress has been made in explaining low-lying level structure for a broad range of nuclei, transition probabilities are not yet quantitatively understood. The ability to understand nuclei far-from-stability is important to astrophysics for extending r- and s-process calculati… more
Date: December 1, 1989
Creator: Firestone, R.B.; Nitschke, J.M.; Wilmarth, P.A.; Vierinen, K.S.; Chasteler, R.M.; Gilat, J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Kaon decay amplitudes using staggered fermions

Description: A status report is given of an attempt, using staggered fermions to calculate the real and imaginary parts of the amplitudes for K ..-->.. ..pi pi..,. Semi-quantitative results are found for the imaginary parts, and these suggest that epsilon' might be smaller than previously expected in the standard model.
Date: December 1, 1986
Creator: Sharpe, S.R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Theoretical Atomic Physics code development IV: LINES, A code for computing atomic line spectra

Description: A new computer program, LINES, has been developed for simulating atomic line emission and absorption spectra using the accurate fine structure energy levels and transition strengths calculated by the (CATS) Cowan Atomic Structure code. Population distributions for the ion stages are obtained in LINES by using the Local Thermodynamic Equilibrium (LTE) model. LINES is also useful for displaying the pertinent atomic data generated by CATS. This report describes the use of LINES. Both CATS and LINE… more
Date: December 1, 1988
Creator: Abdallah, J. Jr. & Clark, R.E.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The status of strange meson spectroscopy

Description: The present status of strange meson spectroscopy is reviewed with emphasis on the results obtained with the LASS spectrometer at SLAC. The systematics of the level structure are discussed with respect to quark model expectations, and the impact of the proposed KAON Factory on the future of the subject considered. 12 refs., 14 figs.
Date: December 1, 1990
Creator: Dunwoodie, W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Inelastic Electron Scattering From Surfaces. Progress Report for Second Grant Year

Description: This report contains highlights of accomplishments of the past year, for the University of California, Irvine and the University of Wisconsin, Milwaukee collaboration on surface excitations, and their interactions with low energy electrons. In addition, we present a summary of future research to be carried out in the coming grant year.
Date: December 31, 1991
Creator: Tong, S. Y. & Mills, D. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Resonant and non-resonant magnetic scattering

Description: The tunability and the polarization of synchrotron radiation open upon new possibilities for the study of magnetism. Studies on magnetic materials performed at the National Synchrotron Light Source are reviewed, and thy fall into four areas: structure, evolution of magnetic order, separation of L and S, and resonance effects. In the vicinity of atomic absorption edges, the Faraday effect, magnetic circular dichroism, and resonant magnetic scattering are all related resonance effects which measu… more
Date: December 31, 1991
Creator: McWhan, D. B.; Hastings, J. B.; Kao, C. C. & Siddons, D. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A tevatron collider beauty factory. [Final report, 1980--1992]

Description: This document which is labeled a final report consists of several different items. The first is a proposal for a detector to be developed for beauty physics. The detector is proposed for the Fermilab Tevatron, and would be designed to measure mixing reactions, rare decay modes, and even CP violation in hadron collider beauty production. The general outline of the work proposed is given, and an estimate of the time to actually design the detector is presented, along with proposed changes to the … more
Date: December 31, 1992
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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