Related papers: Universal pion freeze-out phase-space density
Results on the pion freeze-out phase-space density in sulphur-nucleus, Pb-Pb and pion-proton collisions at CERN-SPS are presented. All heavy-ion reactions are consistent with the thermal Bose-Einstein distrtibution f=1/(exp(E/T)-1) at T~120…
For a class of analytical parametrizations of the freeze-out state of relativistic heavy ion collisions, we perform a simultaneous analysis of the single-particle m_t-spectra and two-particle Bose-Einstein correlations measured in central…
We formulate a freeze-out criterion for ultra-relativistic heavy ion collisions in terms of the pion escape probability from the collision region. We find that the increase in pion phase-space density from SPS to RHIC reported at this…
We explore the consequences of a freeze-out criterion for heavy-ion collisions, based on pion escape probabilities from the hot and dense but rapidly expanding collision region. The influence of the expansion and the scattering rate on the…
We study the role of temperature and density inhomogeneities on the freeze-out of relativistic heavy ion collisions at CERN SPS. Especially the impact on the particle abundancies is investigated. The quality of the fits to the measured…
We analyze the reaction dynamics of central Pb+Pb collisions at 160 GeV/nucleon. First we estimate the energy density pile-up at mid-rapidity and calculate its excitation function: The energy density is decomposed into hadronic and partonic…
Neutral pion production in central 158AGeV Pb+Pb collisions has been studied in the WA98 experiment at the CERN SPS. The pi0 transverse mass spectrum has been analyzed in terms of a thermal model with hydrodynamic expansion. The high…
We propose a method to estimate the entropy of thermal pions in A+A collisions irrespective of unknown form of freeze-out (isothermal) hypersurface and transverse flows developed. We analyse the average phase-space densities and entropies…
We analyse in detail the possibility of Bose-Einstein condensation of pions produced in heavy-ion collisions at the beam energy $\sqrt{s_{\rm NN}}$ = 2.76 TeV. Our approach is based on the chemical non-equilibrium thermal model of hadron…
A method allowing analysis of the overpopulation of phase-space in heavy ion collisions in a model independent way is proposed within the hydrodynamic approach. It makes it possible to extract a chemical potential of thermal pions at freeze…
The strong longitudinal expansion of the reaction zone formed in relativistic heavy-ion collisions is found to significantly reduce the spatially averaged pion phase-space density, compared to naive estimates based on thermal distributions.…
High energy photon emission rate from matter created in Pb + Pb collisions at CERN SPS energies is evaluated. The evolution of matter from the initial state up to freeze-out has been treated within the framework of (3+1) dimensional…
We compute the pion inclusive momentum distribution in a heavy-ion collision, assuming thermal equilibrium and accounting for boundary effects at the time of decoupling. We calculate the chemical potential corresponding to an average pion…
Experimental spectra of the CERN/SPS experiments NA44 and NA49 are fitted while using four different equations of state of nuclear matter within a relativistic hydrodynamic framework. For the freeze-out temperatures, $T_f = 139$ MeV and…
The s-wave correlated $\pi$-$\pi$ strength distribution in cold nuclear matter is investigated. The in-medium single pions are renormalized by means of the usual p-wave couplings to nucleons and $\Delta$'s. Two groups of models for the…
Based on an evaluation of data on pion interferometry and on particle yields at mid-rapidity, we propose a universal condition for thermal freeze-out of pions in heavy-ion collisions. We show that freeze-out occurs when the mean free path…
The centrality dependence of rapidity distributions of pions in Pb+Pb reactions can be understood by imposing local energy-momentum conservation in the longitudinal "fire-streaks" of excited matter. With no tuning nor adjustment to the…
Particle number fluctuations are studied in the ideal pion gas approaching Bose-Einstein condensation. Two different cases are considered: Bose condensation of pions at large charge densities $\rho_Q$ and Bose condensation at large total…
Collisions of cosmic ray particles with ultra-high initial energies with nuclei in the atmosphere open a wide room for appearing of the novel dynamical features for multiparticle production processes. In particular, the pion-lasing behavior…
The space-time structure of the multipion system created in central relativistic heavy-ion collisions is investigated. Using the microscopic transport model UrQMD we determine the freeze-out hypersurface from equation on pion density…