摘要:

We study the charmonium correlators in the deconfined phase, as well as atT<Tc,in two viewpoints. One is an analysis of correlation between quark and antiquark in the finite temperature lattice QCD at the quenched level. The result implies that the correlation is so strong that the quark and antiquark still tend to stay together even atT≃1.5Tc.On the other hand, the potential model analysis, the second approach, results in the existence of no bound state atT≃1.2Tc.The static quark potential obtained in lattice simulation is used in the latter analysis. The change of the bound state energy belowTcis also studied. ©2001 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1425512

出版商:AIP    

年代:1901

数据来源: AIP

摘要:

The physics related to the measurement of the hard probes at RHIC are surveyed through the processes of Drell-Yan pair production, direct &ggr; production, heavy quark production, the inclusive production cross section of the hadrons resulting from the mini-jets, and the identified jets over the varying beam energy and the colliding nuclei. Some of the uncertainties in those measurements can be decided from thep+pprogram. By performing a simple calculation, a few physics possibilities in the coming run are investigated with estimated uncertainties. ©2001 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1425513

出版商:AIP    

年代:1901

数据来源: AIP

摘要:

The extension of the periodic system into various new areas is investigated. Experiments for the synthesis of superheavy elements and the predictions of magic numbers are reviewed. Different ways of nuclear decay are discussed like cluster radioactivity, cold fission and cold multifragmentation, including the recent discovery of the tripple fission of252Cf.Furtheron, investigations on hypernuclei and the possible production of antimatter-clusters in heavy-ion collisions are reported. Various versions of the meson field theory serve as effective field theories at the basis of modern nuclear structure and suggest structure in the vacuum which might be important for the production of hyper- and antimatter. A perspective for future research is given. ©2001 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1425514

出版商:AIP    

年代:1901

数据来源: AIP

摘要:

The properties of the scalar and vector correlations in the hot and/or dense hadronic matter close to chiral transition are discussed. Presuming that the linear realization of chiral symmetry will become appropriate at least near the critical point, we argue that the strength function in theI=J=0channel will soften near the critical point, and the sigma meson will accordingly become a clearer resonance in hot and/or dense medium than in the free space. It is shown that the steep rise of the baryon-number susceptibility&khgr;Baround the critical point seen in the lattice simulations may suggest that the interactions between quarks in the vector channel become week near the critical point; this implies that the peculiar behavior of the&khgr;Bdoes not necessarily imply a proliferation of baryons and antibaryons (Skyrmions) which is though a natural scenario of chiral transition in the non-linear realization of chiral symmetry. ©2001 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1425515

出版商:AIP    

年代:1901

数据来源: AIP

摘要:

Strangeness and flow in heavy ion collisions are discussed. ©2001 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1425516

出版商:AIP    

年代:1901

数据来源: AIP

摘要:

Strangeness production at incident energies close to the elementary production threshold is considered a tool to extract information about the properties of the hot and dense state of nuclear matter produced as a transient state in heavy ion collisions. The production yields and azimuthal anisotropies of strange particles available for nucleus nucleus collisions from the KaoS and FOPI experiments at the SIS accelerator of GSI, Darmstadt, are reviewed with respect to their significance of possible in-medium modifications and their sensitivity to the nuclear equation of state. ©2001 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1425517

出版商:AIP    

年代:1901

数据来源: AIP

摘要:

We discuss the role of the conservation laws related with U(1) internal symmetry group in the statistical model description of particle productions in ultrarelativistic heavy ion collisions. We derive and show the differences in particle multiplicities in the canonical and the grand canonical formulation of quantum number conservation. The time evolution and the approach to chemical equilibrium in the above ensembles is discussed in terms of kinetic master equation. The application of the statistical model to the description of (multi)strange particle yields at GSI/SIS and the SPS energies is also presented. ©2001 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1425518

出版商:AIP    

年代:1901

数据来源: AIP

摘要:

The dual Ginzburg-Landau (DGL) theory corresponding to the SU(3) gluodynamics in Abelian projection is formulated in a Weyl symmetric way. The Weyl symmetric DGL theory can be regarded as the sum of three types of the U(1) dual Abelian Higgs (DAH) model. As an application of this approach, the hadronic flux-tube solution corresponding to the baryonic state is investigated adopting the similar techniques used in the U(1) DAH model. The string representation of the DGL theory is also discussed in a Weyl symmetric way. ©2001 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1425519

出版商:AIP    

年代:1901

数据来源: AIP

摘要:

We study the static three-quark (3Q) potential in detail using SU(3) lattice QCD with123×24at&bgr;=5.7and163×32at&bgr;=5.8,6.0 at the quenched level. For more than 200 patterns of the 3Q systems, we numerically derive 3Q ground-state potentialV3Qfrom the 3Q Wilson loop with the smearing technique, which reduces excited-state contaminations. The lattice QCD data ofV3Qare well reproduced within a few &percent; deviation by a sum of a constant, the two-body Coulomb term and the three-body linear confinement term&sgr;3QLmin,withLminthe minimal value of total length of color flux tubes linking the three quarks. From the comparison with theQ-Q¯potential, we find a universality of the string tension as&sgr;3Q≃&sgr;QQ¯and the one-gluon-exchange result for Coulomb coefficients,A3Q≃1/2AQQ¯.©2001 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1425520

出版商:AIP    

年代:1901

数据来源: AIP

摘要:

The spectra of octet and decuplet baryons are studied usingSU(3)lattice QCD at the quenched level. As an implementation to reduce the statistical fluctuation, we employ the anisotropic lattice withO(a)improved quark action. In relation to &Lgr;(1405), we measure also the mass of theSU(3)flavor-singlet negative-parity baryon, which is described as a three quark state in the quenched lattice QCD, and its lowest mass is measured about 1.6 GeV. Since the experimentally observed negative-parity baryon &Lgr;(1405) is much lighter than 1.6 GeV, &Lgr;(1405) may include a large component of aNK¯bound state rather than the three quark state. The mass splitting between the octet and the decuplet baryons are also discussed in terms of the current quark mass. ©2001 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1425521

出版商:AIP    

年代:1901

数据来源: AIP