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Two exercises in supersymmetry: a low-energy supergravity model and free string field theory

Description: The new features of a supersymmetric standard model in the presence of heavy families are studied. The minimal set of Higgs fields, the desert between the electroweak and the grand unification scale and perturbative values of the dimensionless parameters throughout this region are assumed. Using the numerical as well as the approximate analytic solution of the renormalization group equations, the evolution of all the parameters of the theory are studied in the case of large Yukawa couplings for… more
Date: September 1, 1986
Creator: Preitschopf, C.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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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.
Item Type: Refine your search to only Article
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
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Complementary aspects of potential and quark models for BB and B anti B systems

Description: Our topic at this Round Table is the connection between the particle physics (quark model) and nuclear physics (potential model) approaches to baryonium. This question is part of a larger problem which arises in a variety of contexts in strong interaction physics: how does one reconcile the success of meson (and baryon) exchange models for many low energy hadron-hadron scattering processes with the structure of the underlying quark model. This general problem is discussed, using as examples: (1… more
Date: January 1, 1980
Creator: Dover, C B
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Quarks and gluons in hadrons and nuclei

Description: These lectures discuss the particle-nuclear interface -- a general introduction to the ideas and application of colored quarks in nuclear physics, color, the Pauli principle, and spin flavor correlations -- this lecture shows how the magnetic moments of hadrons relate to the underlying color degree of freedom, and the proton's spin -- a quark model perspective. This lecture reviews recent excitement which has led some to claim that in deep inelastic polarized lepton scattering very little of th… more
Date: December 1, 1989
Creator: Close, F. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Production and decay of heavy top quarks

Description: Experimental evidence indicates that the top quark exists and has a mass between 50 and 200 GeV/c{sup 2}. The decays of a top quark with a mass in this range are studied with emphasis placed on the mass region near the threshold for production of real W bosons. Topics discussed are: (1) possible enhancement of strange quark production when M{sub W} + m{sub s} < m{sub t} < M{sub W} + m{sub b}; (2) exclusive decays of T mesons to B and B{asterisk} mesons using the non-relativistic quark model; (3… more
Date: August 1, 1989
Creator: Kauffman, R.P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Calculations of anti pp. -->. anti yy near threshold

Description: The reactions anti pp ..-->.. anti yy will soon be studied near threshold at LEAR. Comparison of theoretical calculations with the measured differential cross sections, polarizations and spin correlations may help to determine the role of various meson exchange terms and the extent to which quark degrees of freedom are important. Calculations along these lines are in progress and are described briefly.
Date: January 1, 1982
Creator: Eisenstein, R. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Theoretical Studies in Nuclear Reactions and Nuclear Structure

Description: Research in the Maryland Nuclear Theory Group focusses on problems in four basic areas of current relevance. Hadrons in nuclear matter; the structure of hadrons; relativistic nuclear physics and heavy ion dynamics and related processes. The section on hadrons in nuclear matter groups together research items which are aimed at exploring ways in which the properties of nucleons and the mesons which play a role in the nuclear force are modified in the nuclear medium. A very interesting result has … more
Date: May 1, 1992
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Strange-quark-matter stars

Description: We investigate the implications of rapid rotation corresponding to the frequency of the new pulsar reported in the supernovae remnant SN1987A. It places very stringent conditions on the equation of state if the star is assumed to be bound by gravity alone. We find that the central energy density of the star must be greater than 13 times that of nuclear density to be stable against the most optimistic estimate of general relativistic instabilities. This is too high for the matter to consist of i… more
Date: November 1, 1989
Creator: Glendenning, N. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The q q meson states with J sup PC = 2 sup ++ and 0 sup ++

Description: The lowest mesons made up of a light quark and a strange quark produced from a K beam show a good agreement with expectations of the quark model. This good agreement leads to the prediction of the light isoscalar and isovector states and the isoscalar s{bar s} states. Except for one mystery The X(1590) the 2{sup ++} states seems to be well described by the expected ideally mixed q{bar q} states up to 2. 0 GeV. Above 2.0 GeV a new degree of freedom seems to be excited with respect to the breakdo… more
Date: September 26, 1991
Creator: Longacre, R. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Strangeonia and kin; new results from kaon hadroproduction with LASS

Description: Recent results from a high statistics study of strangeonium mesons produced in LASS by an 11 GeV/c K{sup -} beam are reviewed and compared with the quark model. New data from a variety of final states (K*{ovr K*}, {phi}{phi}, {phi}{pi}{sup 0}) produced by hypercharge exchange are described, and compared with results from other hadroproduction modes and from J/{psi} decay. 17 refs., 12 figs.
Date: December 1, 1989
Creator: Aston, D.; Bienz, T.; Bird, F.; Dunwoodie, W.; Johnson, W.B.; Kunz, P. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Gauge invariant description of heavy quark bound states in quantum chromodynamics

Description: A model for a heavy quark meson is proposed in the framework of a gauge-invariant version of quantum chromodynamics. The field operators in this formulation are taken to be Wilson loops and strings with quark-antiquark ends. The fundamental differential equations of point-like Q.C.D. are expressed as variational equations of the extended loops and strings. The 1/N expansion is described, and it is assumed that nonleading effects such as intermediate quark pairs and nonplanar gluonic terms can b… more
Date: August 1, 1980
Creator: Moore, S. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Cabibbo current and CP violation in a six quark gauge model

Description: The extended Cabibbo current in a six quark gauge model is obtained in terms of Eulerian angles theta/sub c/, phi and psi which are functions of quark mass ratios and phases in the quark mass matrices. Particular attention is paid to arbitrary phases that lead to CP violation. In the limit m/sub u//m/sub c/ ..-->.. 0 there is no CP violation for parallel ..delta..S parallel = 1 processes. Some phenomenological results of the model are discussed.
Date: January 1, 1977
Creator: Hagiwara, T.; Kitazoe, T.; Mainland, G. B. & Tanaka, K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Heavy flavor physics at hadron colliders

Description: The search for the top quark has dominated heavy flavor physics at hadron colliders. For Standard model decay of top the present mass limit in m{sub t} > 89 GeV (95% C.L.). Bottom production cross sections are quite large at hadron colliders, thus providing enough statistics for extensive studies. Results on cross sections, B{sup 0} {minus} {bar B}{sup 0} mixing, exclusive channels and rare B decays will be summarized.
Date: December 1, 1991
Creator: Barbaro-Galtieri, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Soft and hard pomerons: Is there a distinction

Description: One of the big unsolved problems of QCD remains the problem of the Pomeron: what is the relation of high energy elastic and diffractive phenomena to the underlying theory This is not a subject in which I have actively worked. But my interest in it has in this year increased greatly. The reason has to do with ideas for experimentation at SSC/LHC which either directly address the problem or which require the understanding of strong-interaction diffractive phenomena as backgrounds for discovery-ph… more
Date: July 1, 1991
Creator: Bjorken, J. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Monte Carlo simulation of a dynamical fermion problem: The light q sup 2 q sup 2 system

Description: We present results from a Guided Random Walk Monte Carlo simulation of the light q{sup 2}{bar q}{sup 2} system in a Coulomb-plus-linear quark potential model using an Intel iPSC/860 hypercube. A solvable model problem is first considered, after which we study the full q{sup 2}{bar q}{sup 2} system in (J,I) = (2,2) and (2,0) sectors. We find evidence for no bound states below the vector-vector threshold in these systems. 17 refs., 6 figs.
Date: January 1, 1991
Creator: Grondin, G. (Toronto Univ., ON (Canada). Dept. of Physics Oak Ridge National Lab., TN (United States))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fragmentation model applied to exclusive final states in photon-photon collisions

Description: Monte Carlo calculations with the Lund string fragmentation model are compared to experimental results on the reactions ..gamma gamma -->..2..pi../sup +/2..pi../sup -/, ..gamma gamma -->..K/sup +/K/sup -/..pi../sup +/..pi../sup -/ and ..gamma gamma -->..p anti p..pi../sup +/..pi../sup -/. It is found, that when the parameters of the Lund model are tuned to low energy, inclusive multi hadron production in photon-photon collisions, the cross sections of exclusive processes near threshold are qual… more
Date: July 1, 1986
Creator: Buijs, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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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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Normalizing the renormalization group in deep inelastic leptoproduction. CTP No. 878

Description: The quark-bag model is used to calculate the nucleon matrix elements of local twist-two operators. Bag matrix elements applicable to low Q/sup 2/ are evolved by use of QCD perturbation theory to a value of Q/sup 2/ large enough that the data can be expected to be dominated by twist-two. Nonsinglet moments of F/sub 3/ are plotted. Although only twist-two was studied, the work has implications for higher twist. It is concluded that either the twist-two operator matrix element is Q/sup 2/ dependen… more
Date: September 1, 1980
Creator: Jaffe, R.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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