Topics on Hydrodynamic Model of Nucleus-Nucleus Collisions

A survey is given on the applications of hydrodynamic model of nucleus-nucleus collisons, focusing especially on i) the resolution of hydrodynamic equations for arbitrary configurations, by using the smoothed-particle hydrodynamic approach; ii) effects of the event-by-event fluctuation of the initial conditions on the observables; iii) decoupling criteria; iv) analytical solutions; and others.Comment: 30 pages, 29 figures; corrected typo

On the necessity to include event-by-event fluctuations in experimental evaluation of elliptical flow

Elliptic flow at RHIC is computed event-by-event with NeXSPheRIO. We show that when symmetry of the particle distribution in relation to the reaction plane is assumed, as usually done in the experimental extraction of elliptic flow, there is a disagreement between the true and reconstructed elliptic flows (15-30% for $\eta$=0, 30% for $p_\perp$=0.5 GeV). We suggest a possible way to take into account the asymmetry and get good agreement between these elliptic flows

Simple solutions of relativistic hydrodynamics for longitudinally expanding systems

Simple, self-similar, analytic solutions of 1+1 dimensional relativistic hydrodynamics are presented, generalizing Bjorken's solution to inhomogeneous rapidity distribution.Comment: 12 pages, elsart.cls, 2 eps figure

Simple solutions of relativistic hydrodynamics for systems with ellipsoidal symmetry

Simple, self-similar, analytic solutions of (1+3)-dimensional relativistic hydrodynamics are presented for ellipsoidally symmetric finite fireballs corresponding to non-central collisions of heavy ions at relativistic bombarding energies. The hydrodynamical solutions are obtained for a new, general family of equations of state with the possibility of describing phase transitions.Comment: 13 pages, no figures, uses elsart.cl

Event-by-event analysis of ultra-relativistic heavy-ion collisions in smoothed particle hydrodynamics

The method of smoothed particle hydrodynamics (SPH) is applied for ultra-relativistic heavy-ion collisions. The SPH method has several advantages in studying event-by-event fluctuations, which attract much attention in looking for quark gluon plasma (QGP) formation, because it gives a rather simple scheme for solving hydrodynamical equations. Using initial conditions for Au+Au collisions at RHIC energy produced by NeXus event generator, we solve the hydrodynamical equation in event-by-event basis and study the fluctuations of hadronic observables such as dN/dy due to the initial conditions. In particular, fluctuations of elliptic flow coefficient v2 is investigated for both the cases, with and without QGP formation. This can be used as an additional test of QGP formation.Comment: LaTeX, 16 figures, 3 tables, 23 pages. Talk presented at 6th International Workshop on Relativistic Aspects of Nuclear Physics(RANP2000), Caraguatatuba, Tabatinga Beach, Sao Paulo, Brazil, October 17-20, 2000. To be published in the proceedings (World Scientific, Singapore

Antihyperon polarization in high-energy inclusive reactions

We propose a model for the antihyperon polarization in high-energy proton-nucleus inclusive reactions, based on the final-state interactions between the antihyperons and other produced particles (predominantly pions). To formulate this idea, we use the previously obtained low-energy pion-(anti-)hyperon interaction using effective chiral Lagrangians, and a hydrodynamic parametrization of the background matter, which expands and decouples at a certain freezeout temperature.Comment: 17 pages, 10 figure