Transversal Flow of Pions as a Consequence of Rescattering Process in non-central Pb+Pb 158GeV/n heavy ion collisions

TL;DR

This paper uses computer simulations to demonstrate that the transverse flow of pions in non-central heavy ion collisions results from rescattering processes and collision geometry, confirming a specific flow pattern predicted by theory.

Contribution

It provides the first simulation-based evidence supporting the parallel squeeze-out transverse flow in non-central Pb-Pb collisions at 158 GeV/n.

Findings

Identification of azimuthal asymmetry in pion distribution

Rescattering as the cause of flow asymmetry

Confirmation of the parallel squeeze-out flow pattern

Abstract

Aim of this work was to test the idea of J.-Y.Ollitrault about the parallel squeeze-out type of transversal flow in mid-rapidity region. For this purpose we have performed a computer simulation of the expanding pion gas created in non-central Pb-Pb 158GeV/n collisions. A squeeze-out type of asymmetry parallel to impact parameter in azimuthal distribution of pions is found and studied. The asymmetry is explained as a consequence of geometry of non-central collisions and the rescattering process.