12 research outputs found
Spectra of produced particles at CERN SPS heavy-ion collisions from a parton-cascade model
We evaluate the spectra of produced particles (pions, kaons, antiprotons) from partonic cascades which may develop in the wake of heavy-ion collisions at CERN SPS energies and which may hadronize by formation of clusters which decay into hadrons. Using the experimental data obtained by NA35 and NA44 collaborations for S+S and Pb+Pb collisions, we conclude that the Monte Carlo implementation of the recently developed parton-cascade/cluster-hadronization model provides a reasonable description of the distributions of the particles produced in such collisions. While the rapidity distribution of the mid-rapidity protons is described reasonably well, their transverse momentum distribution falls too rapidly compared to the experimental values, implying a significant effect of final state scattering among the produced hadrons neglected so far
Correlations and Fluctuations in High-Energy Nuclear Collisions
Nucleon correlations in the target and projectile nuclei are shown to reduce
significantly the fluctuations in multiple nucleon-nucleon collisions, total
multiplicity and transverse energy in relativistic heavy-ion collisions, in
particular for heavy projectile and target. The interplay between cross-section
fluctuations, from color transparency and opacity, and nuclear correlations is
calculated and found to be able to account for large fluctuations in transverse
energy spectra. Numerical implementation of correlations and cross-section
fluctuations in Monte-Carlo codes is discussed.Comment: 30 pages, in Revtex, plus 4 figures. Figures and preprint can be
obtained by mailing address to: [email protected]
High Temperature Matter and Gamma Ray Spectra from Microscopic Black Holes
The relativistic viscous fluid equations describing the outflow of high
temperature matter created via Hawking radiation from microscopic black holes
are solved numerically for a realistic equation of state. We focus on black
holes with initial temperatures greater than 100 GeV and lifetimes less than 6
days. The spectra of direct photons and photons from decay are
calculated for energies greater than 1 GeV. We calculate the diffuse gamma ray
spectrum from black holes distributed in our galactic halo. However, the most
promising route for their observation is to search for point sources emitting
gamma rays of ever-increasing energy.Comment: 33 pages, 13 figures, to be submitted to PR
Relativistic Viscous Fluid Description of Microscopic Black Hole Wind
Microscopic black holes explode with their temperature varying inversely as
their mass. Such explosions would lead to the highest temperatures in the
present universe, all the way to the Planck energy. Whether or not a
quasi-stationary shell of matter undergoing radial hydrodynamic expansion
surrounds such black holes is been controversial. In this paper relativistic
viscous fluid equations are applied to the problem. It is shown that a
self-consistent picture emerges of a fluid just marginally kept in local
thermal equilibrium; viscosity is a crucial element of the dynamics.Comment: 11 pages, revte