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arXiv · 2212.06018

Interplay of longitudinal and transverse expansion in the kinetic dynamics of heavy-ion collisions

Piotr Bozek
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Abstract

The early dynamics in heavy-ion collisions involves a rapid, far from equilibrium evolution. This early pre-equilibrium stage of the dynamics can be modeled using kinetic equations. The effect of this pre-equilibrium stage on final observables derived from transverse momenta of emitted particles is small. The kinetic equations in the relaxation time approximation for a non-boost invariant system are solved. The asymmetry of the flow with respect to the reaction plane at different rapidities is found to be very sensitive to the degree of non-equilibrium in the evolution. This suggests that the rapidity odd directed flow could be studied to identify the occurrence of non-equilibrium effects and to estimate the asymmetry of the pressure between the longitudinal and transverse directions in the collision.

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Piotr Bozek. 2022-12-12. Interplay of longitudinal and transverse expansion in the kinetic dynamics of heavy-ion collisions. https://doi.org/10.1103/physrevc.107.034916

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