318 research outputs found
Electromagnetic Spectrum from QGP Fluid
We calculate thermal photon and electron pair distribution from hot QCD
matter produced in high energy heavy-ion collisions, based on a hydrodynamical
model which is so tuned as to reproduce the recent experimental data at CERN
SPS, and compare these electromagnetic spectra with experimental data given by
CERN WA80 and CERES. We investigate mainly the effects of the off-shell
properties of the source particles on the electromagnetic spectra.Comment: 5 pages, latex, 4 Postscript figures. A talk given at the
International School on the Physics of Quark Gluon Plasma, June 3-6, 1997,
Hiroshima, Japan. To be appeared in Prog. Theor. Phys. Supplemen
Pion Interferometry From A Relativistic Fluid With A First Order Phase Transition In CERN-SPS 158 GeV/A Pb+Pb Collisions
We investigate pion source sizes through the Yano-Koonin-Podgoretski\u{\i}
(YKP) parametrization for the Hanbury-Brown Twiss (HBT) effect in the CERN-SPS
158 GeV/A central collisions. We calculate two-particle correlation functions
numerically based on a (3+1)-dimensional relativistic hydrodynamics with a
first order phase transition and analyze the pair momentum dependence of the
HBT radii extracted from the YKP parametrization in detail. We find that even
in the case of a first order phase transition, expansion and the surface
dominant freeze-out make the source in the hydrodynamical model opaque
significantly. Consequently, the interpretation of the temporal radius
parameter as the time duration becomes unavailable for the hydrodynamical
model.Comment: 5 pages, LaTeX with six eps figures, Contribution to 'International
Workshop XXVIII on Gross Properties of Nuclei And Nuclear Excitations'.
Hirchegg, Austria, Jan 16-22, 200
A calculation of the transport coefficients of hot and dense hadronic matter based on the event generator URASiMA
We evaluate thermodynamical quantities and the transport coefficients of a
dense and hot hadronic matter based on the event generator URASiMA
(Ultra-Relativistic AA collision Simulator based on Multiple Scattering
Algorithm) with periodic boundary conditions. As the simplest example of the
transport coefficients we investigate the temperature dependence and the
chemical potential dependence of the baryon diffusion constant of a dense and
hot hadronic matter.Comment: To appear in the Proceeding of the International Conference on Quark
Nuclear Physics(QNP2000), 21-25 February 2000, Adelaide, Australi
Thermal Photon Emission from QGP fluid
We compare the numerical results of thermal photon distribution from the hot
QCD matter produced by high energy nuclear collisions, based on hydrodynamical
model, with the recent experimental data obtained by CERN WA80. Through the
asymptotic value of the slope parameter of the transverse momentum
distribution, we discuss the characteristic temperature of the QCD fluid.Comment: 16 pages, latex, 8 Postscript figure
Quenched scalar meson correlator with Domain Wall Fermions
We study the singlet and non-singlet scalar-meson masses using domain wall
fermions and the quenched approximation. The singlet mass is found to be
smaller than the non-singlet mass and indicates that the lowest singlet meson
state could be lighter than 1 GeV. The two-point functions for very small quark
masses are compared with expectations from the small-volume chiral perturbation
theory and the presence of fermionic zero modes.Comment: Lattice2002(chiral), 3 page
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