40 research outputs found
Quark-Hadron Mixed Phase
No full textThe concept of a mixed quark-hadron phase is considered. Dynamics of heavy-ion collisins in a large energy range is outlined. Various possible probes of the mixed phase manifestation as well as modern status of experimental signals are discussed
Quantum statistical model of nuclear multifragmentation in the canonical ensemble method
No full textA quantum statistical model of nuclear multifragmentation is proposed. The recurrence equation method used within the canonical ensemble makes the model solvable and transparent to physical assumptions and allows to get results without involving the Monte Carlo technique. The model exhibits the first-order phase transition. Quantum statistics effects are clearly seen on the microscopic level of occupation numbers but are almost washed out for global thermodynamic variables and the averaged observables studied. In the latter case, the recurrence relations for multiplicity distributions of both intermediate-mass and all fragments are derived and the specific changes in the shape of multiplicity distributions in the narrow region of the transition temperature is stressed. The temperature domain favorable to search for the HBT effect is noted
The quark condensate in relativistic nucleus-nucleus collisions
No full textWe compute the modification of the quark condensate in relativistic nucleus-nucleus collisions and estimate the
4-volume, where the quark condensate is small ( 0.1–0.3) using
hadron phase-space distributions obtained with the quark-gluon
string model. As a function of the beam energy the 4-volume rises
sharply at a beam energy (2–5) GeV, remains
roughly constant up to beam energies GeV and rises at
higher energies. At low energies the reduction of the condensate is
mainly due to baryons, while at higher energies the rise of the
4-volume is due to the abundant mesons produced. Based on our
results we expect that moderate beam energies on the order of 10
GeV per nucleon are favourable for studying the restoration of
chiral symmetry in a baryon-rich environment in nucleus-nucleus
collisions
Towards a New Strategy of Searching for QCD Phase Transition in Heavy Ion Collisions
No full text12 pages, latex file, figures available upon requestWe reconsider the Hung and Shuryak arguments in favour of searching for the deconfinement phase transition in heavy ion collisions {\em downward} from the nominal SPS energy, at where the fireball lifetime is the longest one. Using the recent lattice QCD data and the mixed phase model, we show that the deconfinement transition might occur at the bombarding energies as low as . Attention is drawn to the study of the mixed phase of nuclear matter in the collision energy range
Multifragmentation of non-spherical nuclei : preliminary analysis of central Xe + Sn collisions at 50 MeV.A
No full text9 pages, 2 figures; Talk given at the XXVII International Workshop on Gross Properties of Nuclei and Nuclear Excitation, Hirschegg (Austria), January 17 - 23, 1999The influence of shape of expanding and rotating source on various characteristics of the multifragmentation process is studied. The analysis is based on the extension of the statistical microcanonical multifragmentation model. The comparison with the data is done for central Xe+Sn collisions at 50 A MeV as measured by INDRA Collaboration
