Three-component fluid dynamics for the description of energetic heavy-ion reactions

Abstract

The nucleons taking part in heavy ion reaction are considered as a three-component fluid. The first and second components correspond to the nucleons of the target and the projectile, while the thermalized nucleons produced in the Course of the collision belong to the third component. Making use of the Boltzmann equation, hydrodynamical equations are derived. An equation of state for anisotropic nuclear matter obtained from a field theoretical model in mean field approximation is applied in a one dimensional version of the three-component fluid model. The speed of thermalization is analyzed and compared to the results of cascade and kinetic models.[NUCLEAR REACTIONS Relativistic heavy-ion reactions, hydrodynamic description.

Multicomponent transport theoretical approach to ultrarelativistic heavy ion collisions

“…The inclusion of dissipative processes between the components in the three component model allows to give up the simplifying assumption of former three component models [17,18] where it is assumed that a nucleon of component one or two populating the thermalized matter component carries off all its energy and momentum 9 As a consequence of the above assumption the components of projectile and target in the earlier three component model moved with constant velocity and fixed temperature disregarding recoil effects due to the interpenetration of the nuclei 9…”

“…These components can be arbitrarily defined, but their sum should yield the total momentum distribution of a particle species [17] N f(x, p)= ~ fk(x, Pk). (13 k=l Thus conservation laws are in general not existing for the components separately.…”

“…Let us adopt the model description of [17]. The first and second components correspond to the nucleons of the target and projectile, while the thermalized nucleons produced in the course of the collision belong to the third component.…”

“…of (53), the relativistic equivalent of the former three component hydrodynamics [17] is obtained, characterised by a conversion of the incoming nuclear matter into a thermalized matter component and disregarding frictional interactions between the components.…”

The three-dimensional (2 + 1)-fluid model for relativistic nuclear collisions

“…This idea was further developed in [3,7,15]. In [16] a non-relativistic three-fluid model was developed, introducing a third thermalized fluid of stopped baryons. Depending on the strength of the interaction between the target and projectile fluids this model contains the one-fluid model (strong coupling) as well as the two-fluid model (weak coupling) as limiting cases.…”