Relativistic Kinetic Equations for Finite Domains and Freeze-out Problem

The relativistic kinetic equations for the two domains separated by the hypersurface with both space- and time-like parts are derived. The particle exchange between the domains separated by the time-like boundaries generates source terms and modifies the collision term of the kinetic equation. The correct hydrodynamic equations for the ``hydro+cascade'' models are obtained and their differences from existing freeze-out models of the hadronic matter are discussed

Physical mechanism of the (tri)critical point generation

We discuss some ideas resulting from a phenomenological relation recently declared between the tension of string connecting the static quark-antiquark pair and surface tension of corresponding cylindrical bag. This relation analysis leads to the temperature of vanishing surface tension coefficient of the QGP bags at zero baryonic charge density as T_\sigma = 152.9 +- 4.5 MeV. We develop the view point that this temperature value is not a fortuitous coincidence with the temperature of (partial) chiral symmetry restoration as seen in the lattice QCD simulations. Besides, we argue that T_\sigma defines the QCD (tri)critical endpoint temperature and claim that a negative value of surface tension coefficient recently discovered is not a sole result, but should also exist in ordinary liquids at the supercritical temperatures.Comment: Talk given at the Conference "Critical Point and Onset of Deconfinement (CPOD)" that held on August 23 - 29, 2010, JINR, Dubna, Russia. Contains minimal change

Particle Freeze-out and Discontinuities in Relativistic Hydrodynamics

Freeze-out of particles in relativistic hydrodynamics is considered across a 3-dimensional space-time hypersurface. The conservation laws for time-like parts of the freeze-out hypersurface require different values of temperature, baryonic chemical potential and flow velocity in the fluid and in the final particle spectra. We analyze this freeze-out discontinuity and its connection to the shock-wave phenomena in relativistic hydrodynamics.Comment: 6 figure

Exactly Solvable Model for the QCD Tricritcal Endpoint

An inclusion of temperature and chemical potential dependent surface tension into the gas of quark-gluon bags model resolves a long standing problem of a unified description of the first and second order phase transition with the cross-over. The suggested model has an exact analytical solution and allows one to rigorously study the vicinity of the critical endpoint of the deconfinement phase transition. It is found that at the curve of a zero surface tension coefficient there must exist the surface induced phase tranition of the 2-nd or higher order. The present model predicts that the critical endpoint (CEP) of quantum chromodynamics is the tricritical endpoint.Comment: 14 pages, 3 figures, invited talk given at the International Workshop ``Relativistic Nuclear Physics: from Nuclotron to LHC Energies'', Kiev, Ukraine, June 18-22, 200