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in subjects: "Quark Matter"

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Physics of the STAR experiment at the Relativistic Heavy Ion Collider

An overview of the STAR experiment at the Relativistic Heavy Ion Collider is presented. The experiment will concentrate on the measurement of particle production and jet production at midrapidity in a search for the Quark-Gluon Plasma. These hadronic observables will be studied on an event-by-event basis to determine the thermodynamics of single events and to identify special and unusual events. The physics addressed by STAR is discussed.

Date: January 1, 1992

Creator: Harris, J. W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Structure functions and parton distributions

Activities of the structure functions and parton distributions group is summarized. The impact of scheme-dependence of parton distributions (especially sea-quarks and gluons) on the quantitative formulation of the QCD parton model is highlighted. Recent progress on the global analysis of parton distributions is summarized. Issues on the proper use of the next-to-leading parton distributions are stressed.

Date: April 1, 1991

Creator: Olness, F. (Oregon Univ., Eugene, OR (United States). Inst. of Theoretical Science) & Tung, Wu-Ki (Illinois Inst. of Tech., Chicago, IL (United States). Dept. of Physics)

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Status of the theory of QCD plasma

There is mounting evidence, based on many theoretical approaches, that color is deconfined and chiral symmetry is restored at temperatures greater than about 200 MeV. Reasonable estimates of the energy density to be expected in high energy heavy ion collisions suggest that QCD plasma may be formed in the laboratory. Proposed experimental signals may allow us to infer such quantities as the temperature, the quark dispersion relation, the space-time evolution and, perhaps, even the order of the p… more

Date: January 1, 1984

Creator: Kapusta, J. I.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Initial energy density of quark-gluon plasma in relativistic heavy-ion collisions

Recently, there has been considerable interest in the central rapidity region of highly relativistic heavy-ion collisions. Such an interest stems from the possibility of creating hadron matter of high energy density which may exceed the critical energy density for a phase transition between ordinary confined matter and the unconfined quark-gluon plasma. The experimental searches and identification of the quark-gluon plasma may provide a new insight into the question of quark confinement. The es… more

Date: January 1, 1984

Creator: Wong, C.Y.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Relativistic hydrodynamics, heavy ion reactions and antiproton annihilation

The application of relativistic hydrodynamics to relativistic heavy ions and antiproton annihilation is summarized. Conditions for validity of hydrodynamics are presented. Theoretical results for inclusive particle spectra, pion production and flow analysis are given for medium energy heavy ions. The two-fluid model is introduced and results presented for reactions from 800 MeV per nucleon to 15 GeV on 15 GeV per nucleon. Temperatures and densities attained in antiproton annihilation are given.… more

Date: January 1, 1985

Creator: Strottman, D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Quark Matter '87: Concluding remarks

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.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Fluid dynamical model of ultrarelativistic heavy ion collisions

The aim of the present paper is to investigate a phase transition to a quark-gluon plasma. During the phase transition a large portion of the initial kinetic energy is invested in the latent heat. At late expansion stages we gain back this energy as random thermal motion and not as directed collective flow. In the framework of a three-dimensional relativistic fluid dynamical model the sensitivity of dN/sub B/dy, and <p/sup z/a > on the equation of state are pointed out. 13 refs., 3 figs.

Date: January 1, 1988

Creator: Csernai, L.; Gong, M. & Strottman, D. D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Zero temperature quark matter equation of state

An equation of state is computed for a plasma of one flavor quarks interacting through some phenomenological potential, in the Hartree approximation, at zero temperature. Assuming that the confining potential is scalar and color-independent, it is shown that the quarks undergo a first-order mass phase transition. In addition, due to the way screening is introduced, all the thermodynamic quantities computed are independent of the actual shape of the interquark potential. This equation of state i… more

Date: September 1, 1987

Creator: Grassi, F.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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K meson-nucleus interactions: strangeness and nuclear matter

A brief review is provided of some straightforward K-nuclear and ..lambda..-hypernuclear systems. A discussion of less straightforward speculations on H-dibaryons and strange quark matter by many authors, is also given. 28 refs., 6 figs.

Date: January 1, 1985

Creator: Kahana, S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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High nuclear temperatures by antimatter-matter annihilation

It is suggested that the quark-gluon phase be created through the use of antiproton or antideuteron beams. The first advantage to this method, using higher energy antiprotons than 1.5 GeV/c, is that the higher momenta antiprotons penetrate more deeply so that mesons produced are more nearly contained within the nucleus. Another advantage is that the annihilation products are very forward-peaked and tend to form a beam of mesons so that the energy density does not disperse very rapidly. Calculat… more

Date: January 1, 1985

Creator: Gibbs, W.R. & Strottman, D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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An Approximately 4. Pi. Tracking Magnetic Spectrometer for RHIC

A tracking magnetic spectrometer based on large Time Projection Chambers (TPC) is proposed to measure the momentum of charged particles emerging from the RHIC beam pipe at angles larger than four degrees and to identify the particle type for those beyond fifteen degrees with momenta up to 700 MeV/c, which is a large fraction of the final charged particles emitted by a low rapidity quark-gluon plasma.

Date: January 1, 1987

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Studies of relativistic heavy ion collisions

We expect to complete the observations of lepton pairs with incident protons on proton and deuteron targets. The early results indicate an important fraction due to processes other than bremsstrahlung. Further high statistic runs on heavier targets (Ca on Ca) are scheduled for 1992 and possible runs for heavier ions. We expect to participate in the running and analysis for these experiments and help prepare for upgrades of the DLS system. The Hopkins group is an active member of a collaboration… more

Date: August 1, 1991

Creator: Madansky, L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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RHIC spin collaboration

This talk will describe RHIC, the spin-RHIC complex, give examples of our sensitivity, present our goals, and discuss the big remaining problem.

Date: January 1, 1992

Creator: Bunce, G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Relativistic heavy ion research

This report discusses the following topics: antiproton production; Bose-Einstein correlations; high-transverse momentum spectra; strangeness enhancement in heavy ion collisions; search for rare negative secondaries of antiprotons and antinuclei produced in heavy ion collisions; quark matter; and time-of-flight systems test at Brookhaven AGS. (LSP).

Date: January 1, 1992

Creator: Nagamiya, Shoji.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Hadron production in S+nucleus collisions at 200 GeV/nucleon

Central collisions between nuclei at relativistic energies form a hot and dense hadronic system over a large volume. Phenomenological models, as well as QCD calculations on the lattice, predict a phase transition in nuclear matter leading to deconfinement, a state of matter in which quarks and gluons are free to move inside the entire volume of the deconfined region. This new state was given the name of Quark Gluon Plasma (QGP). Based on the conjecture that collisions of heavy nuclei at high en… more

Date: March 1, 1994

Creator: Margetis, S. & Collaboration, NA35

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Relativistic heavy ion collider: Physics and the STAR experiment

An overview of the Relativistic Heavy Ion Collider (RHIC) and its experimental program is presented. The physics capabilities of STAR, one of two large experiments planned for RHIC, are described through simulations of the measurements anticipated in STAR. The STAR experiment will concentrate on hadronic observables in the search for the Quark-Gluon Plasma (QGP). An emphasis will be placed on event-by-event observables in an attempt to extract thermodynamic variables of individual events and to… more

Date: September 1, 1992

Creator: Harris, J. W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Dynamics of high-energy nucleus-nucleus collisions

The authors use a Glauber multiple-collision model to examine the dynamics of nucleus-nucleus collisions. The model introduces a stopping law, which describes how a baryon loses energy in a baryon-baryon collision, and a particle production law, which is based on the baryon energy loss. The model gives results on the longitudinal energy loss which compare well with the recent WA80 experimental data for /sup 16/O on various targets at 60 and 200 GeV per nucleon. The stopping law that is needed t… more

Date: January 1, 1988

Creator: Wong, C. Y. & Lu, Z. D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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The heavy ion program at CERN

During two periods in 1986 and 1987, oxygen ion beams with energies up to 3.2 TeV will be available at the CERN-SPS. A brief review of the five large heavy ion experiments is presented and the different physics addressed by each of the experiments is discussed. 11 refs., 5 figs.

Date: September 30, 1986

Creator: Lissauer, D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Nuclear physics and astrophysics

We have investigated a variety of research topics on the interface of nuclear physics and astrophysics during the past year. We have continued our study of dihyperon states in dense matter and have started to make a connection between their properties in the core of neutron stars with the ongoing experimental searches at Brookhaven National Laboratory. We started to build a scenario for the origin of gamma-ray bursts using the conversion of neutron stars to strange stars close to an active gala… more

Date: September 1, 1992

Creator: Schramm, D. N. & Olinto, A. V.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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The dijet invariant mass at the Tevatron Collider

The differential cross section of the process p + pbar {yields} jet + jet + X as a function of the dijet invariant mass has been measured with the CDF detector at a center of mass energy of 1.8 TeV at the Tevatron Collider in Fermilab. The present analysis is based on the sample of events collected in the 1988/89 run, amounting to a total integrated luminosity of 4.2 pb{sup {minus}1}. A comparison to leading order QCD and quark compositeness predictions is presented as well as a study of the se… more

Date: May 9, 1990

Creator: Giannetti, P. (Istituto Nazionale di Fisica Nucleare, Pisa (Italy))

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Summary of the heavy ion physics sessions at Lake Louise

The intersections between particle and nuclear physics are discussed. Two subcategories of research are discussed. The first is the study of different phases of nuclear matter. This typically refers to understanding the nuclear equation of state from low baryon densities and temperatures (where a liquid-gas phase transition should occur) to the high densities and temperatures where the onset of deconfinement of quarks in nuclear matter is predicted. Beyond this is the second region, that of the… more

Date: June 1, 1986

Creator: Harris, J. W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Double-Pomeron and two-photon processes at RHIC

Double-Pomeron processes have been shown to be an important and novel source of hadron production at moderate energies at the ISR. These processes are expected to provide glue-rich hadrons from 1 GeV to 10 GeV or more, encompassing the states consisting of u, d, s and b quarks. The double-pomeron cross sections for central hadroproduction are calculated for p {times} p and Au {times} Au at RHIC. Two-photon production of hadrons in the central region begins to dominate or at least become compara… more

Date: November 1, 1991

Creator: Chung, S. U.; Weygand, D. P. & Willutzki, H. J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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(Relativistic heavy ion collisions)

This report discusses the following topics: large transverse momentum hadrons in heavy ion collisions at LHC; ECCO -- event generator for soft production in pp collisions; proton-nucleus and nucleus-nucleus collisions; fractal behavior of multiplicity fluctuations; and quark-hadron phase transition. (LSP)

Date: February 1, 1992

Creator: Hwa, R.C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Review of CERN heavy-ion physics

Results from the heavy-ion experiments at the CERN SPS are reviewed in the context of possible formation and identification of a quark-gluon plasma (QGP).

Date: November 1, 1991

Creator: Odyniec, G.

Item Type: Article

Partner: UNT Libraries Government Documents Department