Correlation of the hyperon potential stiffness with hyperon constituents in neutron stars and heavy-ion collisions

• Published in: Physics letters. B 2024-06, Vol.853, p.138658, Article 138658
• Main Authors: Wei, Si-Na, Feng, Zhao-Qing, Jiang, Wei-Zhou
• Format: Article
• Language: English
• Subjects: Heavy-ion collision; Hyperon collective flow and yield; Neutron stars; Relativistic mean-field hyperon potentials
• ISSN: 0370-2693; 1873-2445
• DOI: 10.1016/j.physletb.2024.138658

The breaking of SU(6) symmetry to a more general flavor SU(3) symmetry could serve as a potential explanation for the “hyperon puzzle” of neutron stars by adjusting the hyperon potentials. Specifically, when the soft relativistic mean-field (RMF) Λ hyperon potentials fall within the domains of chiral SU(3) interactions NLO13 with two-body forces, the maximum mass of neutron stars is expected to be lower than 2.0 M⊙, whereas it can exceed 2.0M⊙ if the RMF Λ hyperon potentials are sufficiently stiff to be consistent with those from chiral SU(3) interactions NLO13 with three-body forces. In our investigation involving these two types of Λ hyperon potentials, we explore how the hyperon yields and flows are affected in heavy-ion collisions. We find that the inclusion of hyperon potentials results in better agreement of the Λ directed flows with data but without clear differentiation in the stiffness of the hyperon potentials. Similarly negligent is the disparity in the rapidity distributions of the Λ collective flows predicted by the stiff and soft hyperon potentials. In contrast, the Λ collective flows beyond the central rapidity region turn out to be sensitive to the stiffness of the RMF equation of state (EOS) with the preference of a soft RMF EOS to a stiff one. Notably, the transverse momentum distributions of Λ hyperon production are sensitive to both the stiffness of the RMF EOS and Λ hyperon potential at high transverse momenta.