Is the centrality dependence of the elliptic flow $v_2$ and of the average $<p_T>$ in RHIC experiments more than a Core-Corona Effect?

Abstract

Recently we have shown that the centrality dependence of the multiplicity of different hadron species observed in RHIC and SPS experiments can be well understood in a simple model, dubbed core-corona model. There it is assumed that those incoming nucleons which scatter only once produce hadrons as in pp collisions whereas those which scatter more often form an equilibrated source which decays according to phase space. In this article we show that also kinematical variables like $v_2/{\epsilon }_{part}(N_{part})$ as well as $v_2^i/{\epsilon }_{part}(N_{part})$ and $<p_T^i(N_{part})>$ of identified particles are well described in this model. The correlation of $<p_T^i>$ between peripheral heavy ion collisions and pp collisions for different hadrons, reproduced in this model, questions whether hydrodynamical calculations are the proper tool to describe non-central heavy ion collision. The model explains as well the centrality dependence of $v_2/{\epsilon }_{part}$ of charged particles, considered up to now as an observable which allows to determine the viscosity of the quark gluon plasma. The observed dependence of $v_2^i/{\epsilon }_{part}(N_{part})$ on the particle species is a simple consequence of the different ratios of core to corona particles.

Figure added, text partially rewritten, interpretation of v2 of identified particles

References in corpus (12)

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Cited by in corpus (11)

• Analysing radial flow features in p-Pb and p-p collisions at several TeV by studying identified particle production in EPOS3
• Parton-Hadron-String Dynamics at Relativistic Collider Energies
• Core-corona effect in hadron collisions and muon production in air showers
• Exploring non-equilibrium quark-gluon plasma effects on charm transport coefficients
• Core-corona separation in the UrQMD hybrid model
• Shear viscosity and chemical equilibration of the QGP
• Core-corona interplay in Pb-Pb collisions at $\sqrt{s_{NN}}$=2.76 TeV
• Geometrical scaling for energies available at the BNL Relativistic Heavy Ion Collider to those at the CERN Large Hadron Collider
• Charmonium Production and Corona Effect
• Considerations on the suppression of charged particles and ${\pi }^0$ in high energy heavy ion collisions
• Core - Corona Model analysis of the Low Energy Beam Scan at RHIC (Relativistic Heavy Ion Collider) in Brookhaven (USA)