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A study of low Q/sup 2/ radiative Bhabha scattering

Description: This thesis presents a study of electron-positron scattering, via nearly real photon exchange, where in the process one or more high energy photons are produced. The motivations behind the work are twofold. Firstly, the study is a sensitive test of the theory of electron-photon interactions, quantum electrodynamics. A deviation from the theory could indicate that the electron is a composite particle. Secondly, a thorough understanding of this process is necessary for experiments to be done in t… more
Date: March 1, 1988
Creator: Karlen, D.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Calculation of harmonic radiation and nuclear coupling arising from atoms in strong laser fields

Description: A numerical, time-dependent quantum mechanical model is used to describe the interaction of an isolated ion with an intense applied laser field, including both electron and nuclear degrees of freedom. Calculated results are presented. We find that the model ion radiates in low odd harmonics of the laser frequency, in qualitative agreement with experimental observations. In addition, it radiates strongly in the x-ray region, at frequencies comparable with the electron Rydberg frequency. Such rad… more
Date: January 1, 1988
Creator: Rinker, G.A.; Solem, J.C. & Biedenharn, L.C.
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Partner: UNT Libraries Government Documents Department
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A study of the coupling resonances in the AGS Booster

Description: Analytic method is used to analyze the tracking results for the AGS-BOOSTER lattice. We found the amplitude dependence of the tune is very important in understanding characteristic of the tracking result. With the perturbed tune, the effective second order perturbation theory work very well. The method can be used to analyze the optimized operational condition for the lattice. For the Booster, the analysis suggests that chromaticity of /minus/2 and /minus/5 and a minimum unperturbed tune split … more
Date: January 1, 1988
Creator: Lee, S. Y.; Tepikian, S. & Zhao, X. F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Hard core perturbation theory

Description: A novel perturbative expansion of the dynamic susceptibility about the ground state wave function is proposed. The method uses Liouville perturbation expansions, the Hubbard-Stratonovich transformation of the Hamiltonian with fictitious bosons, projection super-operators and super-duper-operators. The method is especially applicable to the dynamical susceptibility of strongly-interacting systems, where ground state correlation functions and density matrices are available from calculations or ex… more
Date: January 1, 1988
Creator: Silver, R.N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Nonlinear gyrokinetic Maxwell-Vlasov equations using magnetic coordinates

Description: A gyrokinetic formalism using magnetic coordinates is used to derive self-consistent, nonlinear Maxwell-Vlasov equations that are suitable for particle simulation studies of finite-..beta.. tokamak microturbulence and its associated anomalous transport. The use of magnetic coordinates is an important feature of this work as it introduces the toroidal geometry naturally into our gyrokinetic formalism. The gyrokinetic formalism itself is based on the use of the Action-variational Lie perturbation… more
Date: September 1, 1988
Creator: Brizard, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Electromagnetic pair production in relativistic heavy-ion collisions

Description: We survey the production of electron, muon and tauon pairs in collisions between nuclei at ultra-relativistic energies. Such studies enhance our understanding of the role of the vacuum in field theory, and provide essential input for several experimental programs. A variety of models for the nuclear and nucleon form factors have been considered, revealing some degree of sensitivity to assumptions about sub-nuclear structure. We predict that the cross sections, even at high invariant masses and … more
Date: October 4, 1988
Creator: Bottcher, C. & Strayer, M. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Photon-photon collisions

Description: Highlights of the VIIIth International Workshop on Photon-Photon Collisions are reviewed. New experimental and theoretical results were reported in virtually every area of ..gamma gamma.. physics, particularly in exotic resonance production and tests of quantum chromodynamics where asymptotic freedom and factorization theorems provide predictions for both inclusive and exclusive ..gamma gamma.. reactions at high momentum transfer. 73 refs., 12 figs.
Date: July 1, 1988
Creator: Brodsky, Stanley J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Nonperturbative effects of fermions in the SU(2) sector of the standard model

Description: Some nonperturbative effects of fermions in the SU(2) sector of the standard model are studied on the lattice. The results from both analytic studies and numerical simulations with dynamical fermions are presented. Implications for the strongly coupled standard model are discussed. 20 refs.
Date: October 1, 1988
Creator: Lee, I-Hsiu
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Partner: UNT Libraries Government Documents Department
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Developments in sub-barrier reactions

Description: The study of sub-barrier reactions has developed in recent years to include a broad range of interconnected phenomena. The initial discoveries of enhanced sub-barrier fusion cross sections and the attempts to understand them in terms of couplings to other reactions channels have stimulated investigations into all aspects of heavy-ion collisions at low bombarding energies. As a result, new effects have been observed and new ideas are being put forward. The present talk gives an overview of some … more
Date: January 1, 1988
Creator: Landowne, S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Staggering towards a calculation of weak amplitudes

Description: An explanation is given of the methods required to calculate hadronic matrix elements of the weak Hamiltonians using lattice QCD with staggered fermions. New results are presented for the 1-loop perturbative mixing of the weak interaction operators. New numerical techniques designed for staggered fermions are described. A preliminary result for the kaon B parameter is presented. 24 refs., 3 figs.
Date: September 1, 1988
Creator: Sharpe, S.R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Heavy Flavor Production at Fixed Target and Collider Energies

Description: A review is presented of heavy quark production in /bar p/p, p, and pp interactions at fixed target and collider energies. Calculations of total cross sections are described including contributions through next-to-leading order in QCD perturbation theory. Comparisons with available data on charm and bottom quark production show good agreement for reasonable values of charm and bottom quark masses and other parameters. Open issues in the interpretation of results are summarized. A discussion is … more
Date: October 13, 1988
Creator: Berger, E. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Strong uniqueness of best complex Chebyshev approximation to analytic perturbations of analytic function

Description: By studying the strong uniquess properties of best complex Chebyshev approximations to perturbations of a special class of functions, we show that strong uniqueness is not a generic property when we restrict ourselves to nonoscillatory'' functions. 10 refs.
Date: March 8, 1988
Creator: Tang, Ping Tak Peter.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Heavy flavor production

Description: Predictions are presented of total cross sections for charm and bottom quark production in /bar p/p, ..pi../sup /minus//p, and pp interactions at fixed target and collider energies. The calculations are done through next-to-leading order in QCD perturbation theory. The sensitivity is explored of results to the choices of renormalization/evolution scale, parton densities, ..lambda../sub QCD/, and heavy flavor masses. Comparisons with available data show that good agreement is obtained for reason… more
Date: June 10, 1988
Creator: Berger, E. L.
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Partner: UNT Libraries Government Documents Department
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The QCD vacuum at infinite momentum

Description: We outline how ''topological confinement'' can be seen by the analysis of Regge limit infra-red divergences. We suggest that it is a necessary bridge between conventional confinement and the parton model at infinite momentum. It is produced by adding a chiral doublet of color sextet quarks to conventional QCD. An immediate signature of the resultant electroweak symmetry breaking would be large cross-sections for W/sup +/W/sup /minus// and Z/sup 0/Z/sup 0/ pairs at the CERN and Fermilab /bar p/p… more
Date: November 18, 1988
Creator: White, A.R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Phenomenology of Heavy Flavor Production

Description: A review is presented of heavy quark in /bar p/p, p, and pp interactions at fixed target and collider energies. Calculations of total cross sections are described, including contributions through next-to-leading order in QCD perturbation theory. Comparisons with available data on charm and bottom quark production show good agreement for reasonable values of charm and bottom quark masses and other parameters. Open issues in the interpretation of results are summarized. A discussion is presented … more
Date: October 13, 1988
Creator: Berger, E. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Large transverse momentum and higher twist phenomena

Description: A brief summary of the physics of large transverse momentum and higher twist phenomena is given. Particle topics discussed are: higher twist effects in deep inelastic scattering; power suppressed effects at kinematic boundaries; heavy flavour production; vector boson production; and the running of the coupling constant. (LSP)
Date: November 1, 1988
Creator: Ellis, R.K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The status of perturbative QCD

Description: The advances in perturbative QCD are reviewed. The status of determinations of the coupling constant ..cap alpha../sub S/ and the parton distribution functions is presented. New theoretical results on the spin dependent structure functions of the proton are also reviewed. The theoretical description of the production of vector bosons, jets and heavy quarks is outlined with special emphasis on new results. Expected rates for top quark production at hadronic colliders are presented. 111 refs., 8 … more
Date: October 1, 1988
Creator: Ellis, R.K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The application of light-cone quantization to quantum chromodynamics in one-plus-one dimensions

Description: Formal and computational aspects of light cone quantization are studied by application to quantum chromodynamics (QCD) in one spatial plus one temporal dimension. This quantization scheme, which has been extensively applied to perturbative calculations, is shown to provide an intuitively appealing and numerically tractable approach to non-perturbative computations as well. In the initial section, a light-cone quantization procedure is developed which incorporates fields on the boundaries. This … more
Date: December 1, 1988
Creator: Hornbostel, K.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A stochastic method for nuclear power plant diagnosis

Description: The value of using neutron noise descriptors, especially the power spectral densities (PSDs) of ex-core detectors, to monitor core barrel motion and fuel element vibrations in pressurized water reactors (PWRs) is well established. Indeed, in the mid-frequency range (1 to 20 Hz), PWR neutron noise is dominated by vibration peaks in the neutron PSD that result from the motion of reactor internals. A qualitative examination of such descriptors from a 1150 MWE Westinghouse PWR plant, re-examination… more
Date: January 1, 1988
Creator: Perez, R. B. & Wood, R. T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Beam-beam interactions and luminosity considerations in RHIC

Description: The performance of the RHIC machine is largely determined by the intrabeam scattering process. However, beam-beam interactions due to both nuclear scattering and intrinsic Coulomb excitation of the heavy ions will result in beam loss and luminosity reductions. The transverse electric field, responsible for Coulomb excitation, is multiplied by a Lorentz Gamma factor at relativistic energies. For /sup 197/Au beams in RHIC (Lab. Frame) this factor is 108. Once Coulomb excitation has occurred, the … more
Date: January 1, 1988
Creator: Rhoades-Brown, M. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Nonlinear gyrokinetic equations for tokamak microturbulence

Description: A nonlinear electrostatic gyrokinetic Vlasov equation, as well as Poisson equation, has been derived in a form suitable for particle simulation studies of tokamak microturbulence and associated anomalous transport. This work differs from the existing nonlinear gyrokinetic theories in toroidal geometry, since the present equations conserve energy while retaining the crucial linear and nonlinear polarization physics. In the derivation, the action-variational Lie perturbation method is utilized in… more
Date: May 1, 1988
Creator: Hahm, T. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Inclusive production of vector mesons in e/sup +/e/sup minus/ annihilation at. sqrt. s = 29 GeV

Description: This thesis describes the measurement of multiplicities and differential cross-sections of the /rho//sup 0/, K*/sup 0/, and /phi/ in e/sup +/e/sup -/ annihilation at ..sqrt..s = 29 GeV, using data collected by the TPC/2..gamma.. Detector Facility at PEP. The number of vector mesons per event is determined to be N(/rho//sup 0/) = 0.77 +- 0.08 +- 0.15, N(K*/sup 0/ + /bar K/*/sup 0/) = 0.58 +- 0.05 +- 0.11, and N(/phi/) = 0.076 +- 0.010 +- 0.012. These multiplicities are used to find that the rati… more
Date: August 1, 1988
Creator: Edberg, T. K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Nuclear Dependence of Structure Functions in the Shadowing Region of Deep Inelastic Scattering

Description: A discussion of nuclear shadowing in deep inelastic lepton scattering is presented. We show that the parton recombination model suggests that shadowing should begin to occur at larger values of Bjorken x as A increases. This expectation as well as that of weak dependence on Q/sup 2/, and the trend of the x dependence of the shadowing phenomenon are consistent with recent data. Shadowing at small x is combined with nuclear bound state effects, responsible for nuclear dependence at larger x, to p… more
Date: July 27, 1988
Creator: Berger, E. L. & Qiu, Jianwei
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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