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Comparison of models of high energy heavy ion collision. [0. 1 to 2. 0 GeV/nuo, review]

Description: Some of the main theoretical developments on heavy ion collisions at energies (0.1 to 2.0) GeV/nuc are reviewed. The fireball, firestreak, hydrodynamic (1-fluid, 2-fluids), ''row on row'', hard sphere and intranuclear cascades, and classical equations of motion models are discussed in detail. Results are compared to each other and to measured Ne + U ..-->.. p + X reactions.
Date: October 1, 1977
Creator: Gyulassy, M.
Partner: UNT Libraries Government Documents Department

Formation of a quark-gluon plasma in nuclear collisions

Description: The spatial dependence of the energy deposition in the fragmentation regions is estimated for nuclear collisions at ISR energies, ..sqrt..s/A >approx. 30 GeV/nucleon. Two models (the trailing cascade and sequential decay scenarios) are contrasted. The results are compared to the quark-gluon plasma energy density computed via QCD lattice methods.
Date: June 1, 1982
Creator: Gyulassy, M.
Partner: UNT Libraries Government Documents Department

Relativistic nuclear collisions: theory

Description: Some of the recent theoretical developments in relativistic (0.5 to 2.0-GeV/nucleon) nuclear collisions are reviewed. The statistical model, hydrodynamic model, classical equation of motion calculations, billiard ball dynamics, and intranuclear cascade models are discussed in detail. Inclusive proton and pion spectra are analyzed for a variety of reactions. Particular attention is focused on how the complex interplay of the basic reaction mechanism hinders attempts to deduce the nuclear matter equation of state from data. 102 references, 19 figures.
Date: July 1, 1980
Creator: Gyulassy, M.
Partner: UNT Libraries Government Documents Department

Signatures of new phenomena in ultrarelativistic nuclear collisions

Description: Three classes of observables are discussed which may shed light on the properties of the quark-gluon plasma formed in ultrarelativistic nuclear collisions. They are: (1) thermometers: the penetrating probes ..mu../sup +/..mu../sup -/, ..gamma.., c, (2) barometers: transverse flow via <p perpendicular >, and (3) seismometers: fluctuations of dN/dy and dE perpendicular/dy. The need for reliable estimates of the background due to the non-equilibrium processes is emphasized. 49 references.
Date: November 1, 1983
Creator: Gyulassy, M.
Partner: UNT Libraries Government Documents Department

Quark Matter '87: Concluding remarks

Description: This year marked the beginning of the experimental program at BNL and CERN to probe the properties of ultra dense hadronic matter and to search for the quark-gluon plasma phase of matter. Possible implications of the preliminary findings are discussed. Problems needing further theoretical and experimental study are pointed out. 50 refs.
Date: March 1, 1988
Creator: Gyulassy, M.
Partner: UNT Libraries Government Documents Department

Heavy ion physics challenges at Bevalac/SIS energies

Description: This paper discusses where the future of higher energy heavy ion acceleration may lead in terms of understanding the nucleus. The discussion concerns obstacles to formulating an equation of state for nuclear matter at high temperature and density. Implications of this research for astrophysical problems is also presented. (LSP)
Date: November 1, 1987
Creator: Gyulassy, M.
Partner: UNT Libraries Government Documents Department

Pion condensation and instabilities: current theory and experiment

Description: Current calculations of pion condensation phenomena in symmetric nuclear matter are reviewed. The RPA and MFA methods are compared. Latest results (LBL-10572) with a relativistic MFA theory constrained by bulk nuclear properties are presented. The differences between equilibrium (condensation) and nonequilibrium (dynamic) instabilities are discussed. Finally, two-proton correlation experiments aimed at looking for critical scattering phenomena and two-pion correlation experiments aimed at looking for pion field coherence are analyzed. 10 figures, 2 tables.
Date: May 1, 1980
Creator: Gyulassy, M.
Partner: UNT Libraries Government Documents Department

In search of high density collective phenomena in nuclear collision. [0. 2 to 2. 0 GeV/nucleon]

Description: The progress made toward uncovering signatures of collective phenomena is reviewed. Elements of the basic reaction mechanism leading to a complex background are first discussed. Possible hints of collective phenomena in proton and pion single and double inclusive spectra as well as ..pi../sup -/ multiplicity data are then described. 6 figures, 2 tables.
Date: June 1, 1979
Creator: Gyulassy, M.
Partner: UNT Libraries Government Documents Department

Multipion production in nuclear collisions

Description: Two aspects of multipion production in nuclear collisions are discussed: the negative pion multiplicity distribution and the ..pi../sup -/..pi../sup -/ correlation function. The emphasis is on how these observables could be used to search for signals of collective phenomena in nuclear collisions. 2 figures.
Date: March 1, 1979
Creator: Gyulassy, M.
Partner: UNT Libraries Government Documents Department

Non-linear vacuum polarization in strong fields

Description: The Wichmann-Kroll formalism for calculating the vacuum polarization density to first order in ..cap alpha.. but to all orders in Z..cap alpha.. is derived. The most essential quantity is shown to be the electrons Green's function in these calculations. The method of constructing that Green's function in the field of finite radius nuclei is then presented.
Date: July 1, 1981
Creator: Gyulassy, M.
Partner: UNT Libraries Government Documents Department

Space station as quark matter factory

Description: We review the theoretical arguments indicating that hadronic matter dissolves into a quark gluon plasma at energy densities only one order of magnitude above the energy density in nuclei and point out that such energy densities can be achieved in nuclear collisions at 10 to 1000 AGeV. 17 references.
Date: November 1, 1984
Creator: Gyulassy, M.
Partner: UNT Libraries Government Documents Department

Anomalons, honey, and glue in nuclear collisions

Description: In these lectures, selected topics in nuclear collisions in the energy range 10/sup -1/ to 10/sup 3/ GeV per nucleon are discussed. The evidence for anomalous projectile fragments with short mean free paths is presented. Theoretical speculations on novel topological nuclear excitation and on quark-nuclear complexes in connection with anomalons are discussed. Recent tests for pion field instabilities are presented. Then evidence for collective nuclear flow phenomena are reviewed. Global event analysis and cascade simulations are presented. We address the question of whether nuclear flow is like viscous honey. Finally, the criteria for the production of a quark-gluon plasma are discussed. Nuclear stopping power and longitudinal growth at high energies are considered. Results from cosmic ray data show that nuclear collision at TeV per nucleon energies are likely to product a plasma.
Date: December 1, 1982
Creator: Gyulassy, M.
Partner: UNT Libraries Government Documents Department

Coherent pion processes in nuclear collision. [Cross section instabilities, signatures, pion field]

Description: The calculations indicating that pionic instabilities could occur during nuclear collisions are reviewed and specific dynamical effects of such instabilities are discussed. Then experimental signatures of pionic instabilities are considered. The single nucleon inclusive cross section as well as the pion multiplicity distribution are shown not to be sensitive to such instabilities. In particular, no copious pion production is expected. Finally, it is discussed how ..pi../sup -/..pi../sup -/ inclusive cross section can be used as a sensitive tool to measure the degree of coherence of the pion field in nuclear collisions.
Date: April 1, 1978
Creator: Gyulassy, M.
Partner: UNT Libraries Government Documents Department

Current topics in relativistic nuclear collisions

Description: First, current attempts to deduce the nuclear matter equation of state from inclusive data are discussed. Next, some puzzling projectile fragment properties found in emulsions are discussed. Finally, a new test of pion condensation is proposed, and current pion data are reviewed. 11 figures.
Date: August 1, 1980
Creator: Gyulassy, M.
Partner: UNT Libraries Government Documents Department

Nuclear collisions from AMeV to ATeV: from nuclear to quark matter

Description: The maximum energy density achieved in nuclear collisions is estimated in this energy range. Stopping power and longitudinal growth are discussed. We show that for lab energies > 100 AGeV energy densities high enough to produce a plasma can be reached. Cosmic-ray data support these calculations and suggest a possible novel signature of the plasma phase transition.
Date: October 1, 1982
Creator: Gyulassy, M.
Partner: UNT Libraries Government Documents Department

Pionic instabilities in high-energy heavy ion collisions

Description: The study of heavy ion reactions includes the determination of whether pionic instabilities can exist at the densities and excitation energies expected in heavy ion collisions, the calculation of growth rates of unstable pion modes, and the determination of the effect such instabilities would have on the dynamics in heavy ion collisions. 14 references. (JFP)
Date: June 1, 1977
Creator: Gyulassy, M.
Partner: UNT Libraries Government Documents Department

Space-time aspects of hadronic cascading in lepton nucleus scattering

Description: A Monte Carlo model of hadronic cascading in inelastic lepton nucleus scattering is constructed to investigate space-time scenarios consistent with the momentum space description of string models of multiparticle production. The prospects for resolving the ambiguity inherent in the definition of a formation length for composite hadrons are emphasized. 15 refs., 13 figs.
Date: May 1, 1989
Creator: Gyulassy, M. & Pluemer, M.
Partner: UNT Libraries Government Documents Department

COLOR SUPERCONDUCTIVITY, INSTANTONS AND PARITY (NON?)-CONSERVATION AT HIGH BARYON DENSITY-VOLUME 5.

Description: This one day Riken BNL Research Center workshop was organized to follow-up on the rapidly developing theoretical work on color super-conductivity, instanton dynamics, and possible signatures of parity violation in strong interactions that was stimulated by the talk of Frank Wilczek during the Riken BNL September Symposium. The workshop was held on November 11, 1997 at the center with over 30 participants. The program consisted of four talks on theory in the morning followed by two talks in the afternoon by experimentalists and open discussion. Krishna Rajagopal (MIT) first reviewed the status of the chiral condensate calculations at high baryon density within the instanton model and the percolation transition at moderate densities restoring chiral symmetry. Mark Alford (Princeton) then discussed the nature of the novel color super-conducting diquark condensates. The main result was that the largest gap on the order of 100 MeV was found for the 0{sup +} condensate, with only a tiny gap &lt;&lt; MeV for the other possible 1{sup +}. Thomas Schaefer (INT) gave a complete overview of the instanton effects on correlators and showed independent calculations in collaboration with Shuryak (SUNY) and Velkovsky (BNL) confirming the updated results of the Wilczek group (Princeton, MIT). Yang Pang (Columbia) addressed the general question of how breaking of discrete symmetries by any condensate with suitable quantum numbers could be searched for experimentally especially at the AGS through longitudinal A polarization measurements. Nicholas Samios (BNL) reviewed the history of measurements on {Lambda} polarization and suggested specific kinematical variables for such analysis. Brian Cole (Columbia) showed recent E910 measurements of {Lambda} production at the AGS in nuclear collisions and focused on the systematic biases that must be considered when looking for small symmetry breaking effects. Lively discussions led by Robert Jaffe (MIT) focused especially on speculations on the still unknown signatures ...
Date: November 11, 1997
Creator: GYULASSY,M.
Partner: UNT Libraries Government Documents Department

Theory of ultra dense matter and the dynamics of high energy interactions involving nuclei. Progress report, December 15, 1993--December 14, 1994

Description: This report summarizes the progress made during the second year of the three year DOE agreement DE-FG02-93ER40764 on theoretical nuclear physics research performed at the Columbia University and presents a detailed budget adjustment for the third year period December 15, 1994 to December 14, 1995. Sections 1.1 to 1.8 highlight the technical progress made on the following general areas: Multiple scattering and radiative processes in QCD; the quark-gluon plasma transition in nuclear matter; QCD transport theory and dissipative mechanism in dense matter; phenomenological models of high energy interactions involving nuclei; signatures of quark-gluon plasma formation in A+A; neurocomputation theory. Section 2 contains a bibliography of published papers and invited conference papers. Section 3 lists the Columbia nuclear theory members for the December 15, 1994 to December 14, 1995 period. Finally, the budget adjustment requesting $319,830 for the third year relative to the original $320,000 is presented in section 6. Copies of the research papers accompany this report.
Date: September 12, 1994
Creator: Gyulassy, M.
Partner: UNT Libraries Government Documents Department

Theory of ultra dense matter and the dynamics of high energy interactions involving nuclei. Progress report, December 15, 1992--December 14, 1993

Description: Progress in the areas of pQCD radiative processes in dense matter, QCD transport theories to describe the evolution of nonequilibrium phenomena in dense matter, and the development and testing of phenomenological models of high-energy nuclear collisions is summarized. The evolution of the total energy density of quarks and gluons with minijet initial conditions at RHIC energy is shown for Au+Au.
Date: September 15, 1993
Creator: Gyulassy, M.
Partner: UNT Libraries Government Documents Department

PION CONDENSATION IN A FIELD THEORY CONSISTENT WITH BULK PROPERTIES OF NUCLEAR MATTER

Description: Pion condensation is investigated in a self-consistent. relativistic mean field theory that is constrained to reproduce the bulk properties of nuclear matter. This constraint and self-consistency provide stringent constraints on the existence and energy of the condensate.
Date: March 1, 1980
Creator: Banerjee, B.; Glendenning, N.K. & Gyulassy, M.
Partner: UNT Libraries Government Documents Department