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Evolution of Baryon-Free Matter Produced in Relativistic Heavy-Ion Collisions

V. N. Russkikh·Yu. B. Ivanov·E. G. Nikonov·W. Noerenberg·V. D. Toneev
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Abstract

A 3-fluid hydrodynamic model is introduced for simulating heavy-ion collisions at incident energies between few and about 200 AGeV. In addition to the two baryon-rich fluids of 2-fluid models, the new model incorporates a third, baryon-free (i.e. with zero net baryonic charge) fluid which is created in the mid-rapidity region. Its evolution is delayed due to a formation time $τ$, during which the baryon-free fluid neither thermalizes nor interacts with the baryon-rich fluids. After formation it thermalizes and starts to interact with the baryon-rich fluids. It is found that for $τ$=0 the interaction strongly affects the baryon-free fluid. However, at reasonable finite formation time, $τ$=1 fm/c, the effect of this interaction turns out to be substantially reduced although still noticeable. Baryonic observables are only slightly affected by the interaction with the baryon-free fluid.

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V. N. Russkikh, Yu. B. Ivanov, E. G. Nikonov, W. Noerenberg, V. D. Toneev. 2003-12-08. Evolution of Baryon-Free Matter Produced in Relativistic Heavy-Ion Collisions. https://doi.org/10.1134/1.1644024

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