Collective flows of light particles in the Au+Au collision at intermediate energies

TL;DR

This study enhances the UrQMD model with Skyrme functional to analyze light particle flows in Au+Au collisions at intermediate energies, showing good agreement with experimental data and exploring sensitivities to nuclear matter properties.

Contribution

Introduces a Skyrme functional into UrQMD for better modeling of light particle flows in heavy-ion collisions, providing insights into the effects of the equation of state and nucleon-nucleon cross sections.

Findings

Light particle yields and flows are well described by the model.

Flows are sensitive to medium-modified nucleon-nucleon cross sections.

Data constraints on nuclear incompressibility remain limited.

Abstract

The Skyrme potential energy density functional is introduced into the Ultrarelativistic Quantum Molecular Dynamics (UrQMD) model and the updated version is applied to studying the directed and elliptic flows of light particles (protons, neutrons, deuterons, tritons, $^3$He and $^4$He) in $^{197}$Au+$^{197}$Au collisions at beam energies 150, 250 and 400 MeV/nucleon. The results are compared with the recent FOPI experimental data. It is found that the yields and collective flows of light particles can be described quite well. The influence of the equation of state (EoS), medium-modified nucleon-nucleon elastic cross sections (NNECS) and cluster recognition criteria on the directed and elliptic flows is studied in detail. It is found that the flows of light particles are sensitive to the medium-modified NNECS, but not sensitive to the isospin dependent cluster recognition criteria. It seems difficult, however, even with the new data and calculations, to obtain a more accurate constraint on the nuclear incompressibility $K_0$ than the interval 200-260 MeV.