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arXiv · 2404.03424

Information entropy for central $^{197}$Au+$^{197}$Au collisions with the ultrarelativistic quantum molecular dynamics model

Xian-Gai Deng·Yu-Gang Ma
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Abstract

This study investigates the multiplicity information entropy of hadrons, anti-hadrons, baryons, and net-protons in central \(^{197}\)Au+\(^{197}\)Au collisions with impact parameters of 0$-$3 fm, using the ultrarelativistic quantum molecular dynamics model (UrQMD) across various center-of-mass energies (\(\sqrt{s_{\rm NN}}\)) from 5.0 to 54.4 GeV. Our simulations employ hydrodynamic modes with different equations of state (EoS) and a default mode without hydrodynamics. The results reveal that the information entropies of baryons and net-protons are sensitive to the selected EoS. In particular, enhancements of the information entropies around \(\sqrt{s_{\rm NN}} \sim 30\) GeV, especially with chiral hadron gas and Bag model EoS, indicate a phase transition or critical endpoint behavior. These findings highlight the importance of the EoS in understanding the thermodynamic properties of matter produced in high-energy collisions.

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Xian-Gai Deng, Yu-Gang Ma. 2025-01-30. Information entropy for central $^{197}$Au+$^{197}$Au collisions with the ultrarelativistic quantum molecular dynamics model. https://doi.org/10.1103/physrevc.111.014904

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