5 research outputs found
- nucleus bound states in Walecka model
Possible formation of nucleus bound state is studied in the framework
of Walecka model. The bound states are found in different nuclei ranging from
to . These bound states may have a direct bearing on the
recent experiments on the photoproduction of meson in the nuclear
medium.Comment: RevTeX fil
Photon Production from a Quark--Gluon Plasma
In-medium interactions of a particle in a hot plasma are considered in the
framework of thermal field theory. The formalism to calculate gauge invariant
rates for photon and dilepton production from the medium is given. In the
application to a QED plasma, astrophysical consequences are pointed out. The
photon production rate from strongly interacting quarks in the quark--gluon
plasma, which might be formed in ultrarelativistic heavy ion collisions, is
calculated in the previously unaccessible regime of photon energies of the
order of the plasma temperature. For temperatures below the chiral phase
transition, an effective field theory incorporating dynamical chiral symmetry
breaking is employed, and perturbative QCD at higher temperatures. A smooth
transition between both regions is obtained. The relevance to the soft photon
problem and to high energy heavy ion experiments is discussed.Comment: Paper in ReVTeX. Figures and complete paper available via anonymous
ftp, ftp://tpri6c.gsi.de/pub/phenning/hq95ga
Equation of State, Radial Flow and Freeze-out in High Energy Heavy Ion Collisions
We have shown that recent experimental data on radial flow, both from AGS and
SPS energies, are in agreement with the Equation of State (EOS) including the
QCD phase transition. New hydro-kinetic model (HKM) is developed, which
incorporates hydrodynamical treatment of expansion and proper kinetics of the
freeze-out. We show that the freeze-out surfaces for different secondaries and
different collisions are very different, and they are not at all isotherms (as
was assumed in most previous hydro works). Comparison of HKM results with
cascade-based event generator RQMD is also made in some details: we found that
both EOS and flow are in rather good agreement, while the space-time picture is
still somewhat different