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Bag model, the hyperspherical formalism and the heavy baryons

Description: The bag model framework is used to discuss the heavy baryons, triple flavored objects like ccc, cbb, etc. A nonrelativistic picture seems justified. It is insisted that the long-range interaction consist of a genuine three-body force. Once the potential energy of the three quarks is determined, the three-body Schroedinger equation is solved by the method of hyperspherical expansion. 1 table. (RWR)
Date: January 1, 1980
Creator: Richard, J. M.
Partner: UNT Libraries Government Documents Department
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Recent experimental results on the beam-beam effects in storage rings and an attempt of their interpretation

Description: The latest available experimental results on the luminosity, the space charge parameters, and the beam blowup as functions of particle energy and beam current are reviewed. The comparison with the phenomenological diffusion theory is done and useful scaling laws are derived. Some implications for anti p p storage rings are discussed.
Date: June 1, 1980
Creator: Kheifets, S.
Partner: UNT Libraries Government Documents Department
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Resource capture by single leaves

Description: Leaves show a variety of strategies for maximizing CO{sub 2} and light capture. These are more meaningfully explained if they are considered in the context of maximizing capture relative to the utilization of water, nutrients and carbohydrates reserves. There is considerable variation between crops in their efficiency of CO{sub 2} and light capture at the leaf level. Understanding of these mechanisms indicate some ways in which efficiency of resource capture could be level cannot be meaningfull… more
Date: May 1, 1992
Creator: Long, S.P.
Partner: UNT Libraries Government Documents Department
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Statistical magnetohydrodynamics and reversed-field-pinch quiescence

Description: A statistical model of a bounded, incompressible, cylindrical magnetofluid is presented. This model predicts the presence of magnetic fluctuations about a cylindrically-symmetric, Bessel-function-model, mean magnetic field, which satisfies del x <B> = ..mu.. <B>. As theta ..-->.. 1.56, the model predicts that the significant region of the fluctuation spectrum narrows down to a single (coherent) m = 1 mode. An analogy between the Debye length of an electrostatic plasma and ..mu../sup -1/ suggest… more
Date: January 1, 1982
Creator: Turner, L.
Partner: UNT Libraries Government Documents Department
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Validation and sensitivity of a simulated photograph technique for visibility modeling

Description: The Los Alamos Scientific Laboratory (LASL) visibility model is capable of producing simulated before and after pictures that illustrate visual effects of smoke plumes. Although the model has been under development for a few years, until recently there had been very little testing of the model against field experience or testing of sensitivity of the model results to numerical approximations used in the model. Further validation and sensitivity testing of the LASL model began in late 1979. The … more
Date: January 1, 1980
Creator: Williams, M.; Chan, L.Y. & Lewis, R.
Partner: UNT Libraries Government Documents Department
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The (t,d) reaction on the Ni isotopes with polarized tritons

Description: The (t vector,d) reaction has been measured on targets of /sup 58/ /sup 60/ /sup 62/ /sup 64/Ni with 17 MeV polarized tritons. Spectroscopic factors, angular momentum and total spin transfer were obtained from the differential cross section and A/sub y/ values of levels up to 3.5 MeV in excitation energy. The present (t,d) measurement enables a better description of the 9/2/sup +/ and 5/2/sup +/ states which show significant shell crossing effects as a function of increasing neutron number.
Date: January 1, 1980
Creator: Flynn, E. R.; Cizewski, J. A.; Brown, R. E.; Hardekopf, R. A. & Sunier, J. W.
Partner: UNT Libraries Government Documents Department
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Alignment and orientation in ion/endash/atom collisions

Description: Recent progress in the theoretical study of alignment and orientation in atom-atom and ion-atom collisions at intermediate energies is reviewed. Recent systematic studies of the alignment and orientation of electronic charge cloud distributions of excited states resulting from such collisions clearly have provided more detailed information about the underlying collision dynamics. However, since accurate determination of these parameters is quite difficult, both theoretically and experimentally,… more
Date: January 1, 1987
Creator: Kimura, M. & Lane, N.F.
Partner: UNT Libraries Government Documents Department
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Stochastic model of radioiodine transport

Description: A research project has been underway at the Oak Ridge National Laboratory with the objective to evaluate dose assessment models and to determine the uncertainty associated with the model predictions. This has resulted in the application of methods to propagate uncertainties through models. Some techniques and results related to this problem are discussed.
Date: January 1, 1980
Creator: Schwarz, G. & Hoffman, F.O.
Partner: UNT Libraries Government Documents Department
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Approach to decision modeling for an ignition test reactor

Description: A comparison matrix decision model is applied to candidates for a D-T ignition tokamak (TNS), including assessment of semi-quantifiable or judgemental factors as well as quantitative ones. The results show that TNS is mission-sensitive with a choice implied between near-term achievability and reactor technology.
Date: September 30, 1977
Creator: Howland, H.R. & Varljen, T.C.
Partner: UNT Libraries Government Documents Department
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Kaon-nucleus interactions

Description: The recent progress in hypernuclear physics, in particular the studies of ..lambda.. and ..sigma.. states via the strangeness-exchange (K/sup -/,..pi../sup -/) reaction, are reviewed. Prospects for future investigations with (proposed) intense kaon beams are also evaluated, for instance the production of high spin hypernuclei via the (..pi../sup +/,K/sup +/) reaction, and the formation of strangeness S = -2 hypernuclei (..lambda lambda.. or Xi/sup -/) by means of the (K/sup -/,K/sup +/) process… more
Date: January 1, 1980
Creator: Dover, C B
Partner: UNT Libraries Government Documents Department
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Development of a mathematical model of a packed column for benzene removal from salt solutions

Description: A mathematical model of a packed column was developed to describe the removal of benzene from radioactive salt solutions at the Savannah River Site. The model was developed from existing, generalized mass transfer correlations for randomly dumped packing, and the correlations were adapted for structured packing. Thermophysical data specific to the solutions of interest were incorporated into the model. Verification of the code was completed using operating data from stripping columns at other l… more
Date: January 1, 1989
Creator: Georgeton, G.K.
Partner: UNT Libraries Government Documents Department
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Structure functions: Their status and implications

Description: I discuss the current status of structure functions. Attention is given to the uncertainties in them and the implications of these uncertainties for experimental predictions. I indicate which experiments are capable of removing these uncertainties. 17 refs., 17 figs., 1 tab.
Date: September 29, 1988
Creator: Hinchliffe, I.
Partner: UNT Libraries Government Documents Department
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Potential energy for quarks

Description: It is argued on theoretical and phenomenological grounds that confinement of quarks is intrinsically a many-body interaction. The Born-Oppenheimer approximation to the bag model is shown to give rise to a static potential energy that consists of a sum of two-body Coulomb terms and a many-body confining term. Following the success of this potential in heavy Q anti Q systems it is being applied to Q/sup 2/ anti Q/sup 2/. Preliminary calculations suggest that dimeson bound states with exotic flavo… more
Date: January 1, 1985
Creator: Heller, L.
Partner: UNT Libraries Government Documents Department
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Two-photon physics

Description: A new experimental frontier has recently been opened to the study of two photon processes. The first results of many aspects of these reactions are being presented at this conference. In contrast, the theoretical development of research ito two photon processes has a much longer history. This talk reviews the many different theoretical ideas which provide a detailed framework for our understanding of two photon processes.
Date: October 1, 1981
Creator: Bardeen, W.A.
Partner: UNT Libraries Government Documents Department
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Quark-diagram classification of charm decays

Description: The decays of charm mesons are described in terms of quark-diagram amplitudes. Experimental implications of these amplitudes are also discussed.
Date: May 1, 1980
Creator: Rizzo, T. G. & Wang, L. L.
Partner: UNT Libraries Government Documents Department
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Potential effects of maternal contribution on egg and larva population dynamics of striped bass: Integrated individual-based model and directed field sampling

Description: We have used a bioenergetically-driven, individual-based model (IBM) of striped bass as a framework for synthesizing available information on population biology and quantifying, in a relative sense, factors that potentially affect year class success. The IBM has been configured to simulate environmental conditions experienced by several striped bass populations; i.e., in the Potomac River, MD; in Hudson River, NY; in the Santee-Cooper River System, SC, and; in the San Joaquin-Sacramento River S… more
Date: January 1, 1991
Creator: Cowan, J.H., Jr. (Maryland Univ., Solomons, MD (United States). Chesapeake Biological Lab.) & Rose, K.A. (Oak Ridge National Lab., TN (United States))
Partner: UNT Libraries Government Documents Department
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Aspects of model selection in multivariate analyses

Description: Analysis of data sets that involve large numbers of variables usually entails some type of model fitting and data reduction. In regression problems, a fitted model that is obtained by a selection process can be difficult to evaluate because of optimism induced by the choice mechanism. Problems in areas such as discriminant analysis, calibration, and the like often lead to similar difficulties. The preceeding sections reviewed some of the general ideas behind assessment of regression-type predic… more
Date: January 1, 1982
Creator: Picard, R.
Partner: UNT Libraries Government Documents Department
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Pressure losses in fracture-dominated reservoirs: the wellbore constriction effect

Description: Improved energy production from many types of energy reservoirs such as hot dry rock geothermal as well as hydraulically fractured oil, gas, and other geothermal reservoirs requires a better understanding of the fluid mechanics in the vicinity of the fracture-wellbore intersection. Typically, the aperture (smallest dimension) of a hydraulic fracture is only of the order of 1 mm (0.04 in.) so that reasonable energy production rates from geothermal systems require fairly large flow velocities wit… more
Date: January 1, 1980
Creator: Murphy, H.
Partner: UNT Libraries Government Documents Department
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Simulation of chlorinated water discharges from power plants on estuaries and rivers

Description: The fast-transient (tidal-transient) one-dimensional discrete-element chemical transport model and its associated computer code CHMONE were applied to study the effects of chlorinated water discharges from power plants on tidal estuaries and controlled rivers. The mathematical model has the capability to predict simultaneously the hydrodynamic, thermal, and chemical composition of water as one-dimensional time-dependent distributions. (LTW)
Date: January 1, 1977
Creator: Eraslan, A. H.; Lietzke, M. H.; Fischer, S. K. & Kalmaz, E. V.
Partner: UNT Libraries Government Documents Department
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Light composite fermions: an overview

Description: Some rules which have been proposed, including 't Hooft's anomaly conditions, decoupling conditions and tumbling versus no tumbling are discussed. Then mass generation mechanisms for composite fermions are covered, including weak gauging, strong gauging, and unification. The origin of the different generations of quarks and leptons is then considered. In the context of composite models, the three generations of quarks and leptons must appear in the first approximation as three sets of massless … more
Date: January 1, 1982
Creator: Raby, S.
Partner: UNT Libraries Government Documents Department
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A theoretical prediction of critical heat flux in subcooled pool boiling during power transients

Description: Understanding and predicting critical heat flux (CHF) behavior during steady-state and transient conditions are of fundamenatal interest in the design, operation, safety of boiling and two-phase flow devices. This paper discusses the results of a comprehensive theoretical study made specifically to model transient CHF behavior in subcooled pool boiling. This study is based upon a simplified steady-state CHF model in terms of the vapor mass growth period. The results obtained from this theory in… more
Date: January 1, 1988
Creator: Pasamehmetoglu, K. O.; Nelson, R. A. & Gunnerson, F. S.
Partner: UNT Libraries Government Documents Department
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A semi-analytical method for heat sweep calculations in fractured reservoirs

Description: An analytical approximation is developed for purely conductive heat transfer from impermeable blocks of rock to fluids sweeping past the rocks in fractures. The method was incorporated into a multi-phase fluid and heat flow simulator. Comparison with exact analytical solutions and with simulations using a multiple interacting continua approach shows very good accuracy, with no increase in computing time compared to porous medium simulations. 14 refs., 3 figs., 5 tabs.
Date: January 1, 1988
Creator: Pruess, K. & Wu, Y.S.
Partner: UNT Libraries Government Documents Department
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