6 research outputs found
Photon emission in Pb+Pb collisions at SpS and LHC
Yield of direct photons in Pb+Pb collisions at SpS and LHC energy is
evaluated with emphasis on estimate of possible uncertainty. Possibility of
experimental observation of direct photons at LHC is discussed. Predictions of
several models at SpS energy are compared with experimental data.Comment: 19 pages, 13 figure
Direct emission of light mesons from quark-gluon plasma surface
On the basis of hydrodynamic model of evolution of heavy ion collision we
consider emission of mesons directly from the
surface of quark-gluon plasma, with accounting of their absorption by
surrounding plasma hadronic gas. We evaluate upper and lower limits on yields
of these direct mesons in Pb+Pb collision at 158 AGeV (SpS) and 3150+3150 AGeV
(LHC), and find, that even in the case of the lowest yield, direct and
heavier mesons dominate at LHC energy at soft (). This
enhancement of the low meson production can be considered as a
quark-gluon plasma signature.Comment: Submitted to PR
Thermal Radiation from Au + Au Collisions at \sqrt{s} = 200 GEV/A Energy
The transverse momentum distribution of the direct photons measured by the
PHENIX collaboration in collisions at GeV/A has been
analyzed. It has been shown that the data can be reproduced reasonably well
assuming a deconfined state of thermalized quarks and gluons with initial
temperature more than the transition temperature for deconfinement inferred
from lattice QCD. The value of the initial temperature depends on the equation
of state of the evolving matter. The sensitivities of the results on various
input parameters have been studied. The effects of the modifications of
hadronic properties at non-zero temperature have been discussed.Comment: minor modifications in the text, accepted for publicatio