The VII-th International Conference on the Initial Stages of High-Energy Nuclear Collisions : Initial Stages 2023

Effects of a pre-equilibrium phase in isobar collision systems

Not scheduled

2h

Københavns Universitetsbibliotek Nord

Poster The initial stages and nuclear structure in heavy-ion collisions Reception and poster session

Speaker

Willian Matioli Serenone (Universidade de São Paulo)

Description

The collisions of $^{96}_{44}$Ru+$^{96}_{44}$Ru and $^{96}_{40}$Zr+$^{96}_{40}$Zr performed at RHIC in 2018, albeit originally intended for the search of the chiral magnetic effect, showed that high-energy heavy-ion collisions could be used as a high-precision tool to probe nuclear structure. One typically models such collision as an initial energy deposition in the vacuum, whose distribution will be sensitive to the nuclear structure of the colliding nuclei. The initial energy-density distribution is then used to initialize hydrodynamic-based hybrid simulations. Alternatively, it is possible to correlate final-state observables (such as anisotropic flow) to characteristics of the initial state, as shown in, e.g. [1-3]. However, these ``mapping'' studies typically relate initial states of hydrodynamics to final-states, often neglecting the possible effects of a pre-equilibrium phase. A common choice for such early out-of-equilibrium dynamics is the free-streaming of massless partons. Due to the lack of interaction in this model, one expects it to be the one where loss of information about the initial geometry is bigger. Hence, it is not trivial that it will not adversely affect study of nuclear structure by erasing detailed information of the initial condition. In this work, we study the effects of free-streaming in the isobar systems for different initial state estimators, such as eccentricity, system size, momentum anisotropy and correlation between such quantities.

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doi:10.1103/PhysRevC.93.014909 [arXiv:1511.03896 [nucl-th]].
[2] G. Giacalone, F. G. Gardim, J. Noronha-Hostler and J. Y. Ollitrault, Phys. Rev. C 103, no.2, 024909 (2021)
doi:10.1103/PhysRevC.103.024909 [arXiv:2004.01765 [nucl-th]].
[3] M. Hippert, J. G. P. Barbon, D. Dobrigkeit Chinellato, M. Luzum, J. Noronha, T. Nunes da Silva, W. M. Serenone and
J. Takahashi, Phys. Rev. C 102, no.6, 064909 (2020) doi:10.1103/PhysRevC.102.064909 [arXiv:2006.13358 [nucl-th