Pushing the hybrid approach to low beam energies with dynamic initial conditions from hadronic transport

TL;DR

This paper introduces dynamic initial conditions for viscous hydrodynamics in low to intermediate energy heavy-ion collisions, improving modeling accuracy and aligning well with experimental data.

Contribution

It presents a novel method for setting initial conditions in hybrid hydrodynamic-transport models at lower energies, enhancing the description of heavy-ion collisions.

Findings

Good agreement with bulk observables at 3-9.1 GeV energies

Effective modeling guidance for STAR-BES and CBM experiments

Advancement in low-energy collision simulations

Abstract

While hybrid approaches of relativistic hydrodynamics+transport have been well established for the dynamical description of heavy-ion collisions at high beam energies, moving to lower beam energies is challenging. In this work, we propose dynamic initial conditions for the viscous hydrodynamic evolution in heavy-ion collisions at low to intermediate beam energies. They are comprised of core hadrons based on the local energy density during the pre-equilibrium hadronic evolution. The SMASH-vHLLE hybrid approach is then applied to lower beam energies, achieving good agreement with measured bulk observables between $\sqrt{s_\mathrm{NN}} = 3$ and $9.1\ \mathrm{GeV}$, thus providing guidance for measurements in STAR-BES and CBM at FAIR.