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Probing the nuclear equation of state with clusters and hypernuclei

Yingjie Zhou1,*, Susanne Gläßel2, Yue-Hang Leung3, Viktar Kireyeu4, Jiaxing Zhao5,6, Hui Liu7, Christoph Blume2,1,5, Iouri Vassiliev1, Vadim Voronyuk4 et al.

Michael Winn8, Norbert Herrmann3,1, Yaping Wang9, Nu Xu9,10, Jörg Aichelin8,11, and Elena Bratkovskaya1,5,6

  • *Contact author: z.yingjie@gsi.de
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Phys. Rev. C 113, 014909 – Published 16 January, 2026

DOI: https://doi.org/10.1103/3msm-wrxd

Abstract

The study of the nuclear equation of state (EoS) is one of the primary goals of experimental and theoretical heavy-ion physics. The comparison of recent high-statistics data from the STAR Collaboration with transport models provides a unique possibility to address this topic in a yet-unexplored energy domain. Employing the microscopic N-body parton-hadron-quantum-molecular dynamics transport approach, which allows us to describe the propagation and interactions of hadronic and partonic degrees of freedom, including cluster and hypernucleus formation and dynamics, we investigate the influence of different EoS on bulk observables, the multiplicity, pT, and rapidity distributions of protons, Λs and clusters up to A = 4, as well as their influence on the collective flow. We explore three different EoS: two static EoS, dubbed “soft” and “hard,” which differ in the compressibility modulus, as well as a soft momentum-dependent EoS. We find that a soft momentum-dependent EoS reproduces most baryon and cluster observables, including the flow observables, quantitatively; however, hard EoS show a similar trend.

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Phys. Rev. C 113, 014909– Published 16 January, 2026
  • Received 22 July 2025
  • Accepted 1 December 2025
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