Abstract
Simulations of peripheral \({\text{Au}} + {\text{Au}}\) collisions at NICA energies are performed in the PHSD transport model. The properties of velocity and vorticity fields, as well as hydrodynamic helicity, are studied in dependence on the impact parameter and energy. There is a region of the velocity field that follows the Little Bang pattern, which may be quantified by Hubble’s law. Quadrupole structures of the vorticity field in all planes are obtained. The effect of helicity separation is found in the PHSD model. A calculation of \(\Lambda \)‑hyperon polarization is performed in the thermodynamic and anomalous models at NICA energies.
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REFERENCES
L. Adamczyk et al. (STAR Collab.), “Global Λ hyperon polarization in nuclear collisions: evidence for the most vortical fluid,” Nature 548, 62–65 (2017). arXiv: 1701.06657.
A. Sorin and O. Teryaev, “Axial anomaly and energy dependence of hyperon polarization in heavy-ion collisions,” Phys. Rev. C 95, 011902 (2017). arXiv: 1606.08398.
K. Fukushima, D. E. Kharzeev, and H. J. Warringa, “The chiral magnetic effect,” Phys. Rev. D 78, 074033 (2008). arXiv:0808.3382 [hep-ph].
J. H. Gao, Z. T. Liang, S. Pu, Q. Wang, and X. N. Wang, “Chiral anomaly and local polarization effect from quantum kinetic approach,” Phys. Rev. Lett. 109, 232301 (2012). arXiv:1203.0725 [hep-ph].
W. Cassing and E. L. Bratkovskaya, “Parton-hadron-string dynamics: an off-shell transport approach for relativistic energies,” Nucl. Phys. A 831, 215 (2009). arXiv: 0907.5331 [nucl-th].
A. Zinchenko, A. Sorin, O. Teryaev, and M. Baznat, “Vorticity structure and polarization of Λ hyperons in heavy-ion collisions,” J. Phys. Conf. Ser. 1435, 012030 (2020).
A. Zinchenko, O. Teryaev, M. Baznat, and A. Sorin, “Polarization of Λ -hyperons, vorticity and helicity structure in heavy-ion collisions,” J. Phys. Conf. Ser. 1435, 012030 (2022).
O. Rogachevsky, A. Sorin, and O. Teryaev, “Chiral vortaic effect and neutron asymmetries in heavy-ion collisions,” Phys. Rev. C 82, 054910 (2010). arXiv: 1006.1331 [hep-ph].
M. Baznat, K. Gudima, A. Sorin, and O. Teryaev, “Helicity separation in heavy-ion collisions,” Phys. Rev. C 88, 061901 (2013). arXiv:1301.7003 [nucl-th].
F. Becattini, L. Bucciantini, E. Grossi, and L. Tinti, “Local thermodynamical equilibrium and the beta frame for a quantum relativistic fluid,” Eur. Phys. J. C 75, 191 (2015). arXiv:1403.6265 [hep-th].
ACKNOWLEDGMENTS
We thank E. Bratkovskaya, Yu. Ivanov, E. Kolomeitsev, V. Toneev, V. Voronyuk, and A. Parkhomenko for discussing the results.
Funding
This work was partly supported by the Russian Foundation for Basic Research, grant no. 20-32-90205.
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Baznat, M., Teryaev, O.V. & Zinchenko, A.V. Polarization of Λ Hyperons in Gold Nucleus Collisions at NICA Energies. Phys. Part. Nuclei Lett. 20, 407–411 (2023). https://doi.org/10.1134/S154747712303010X
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DOI: https://doi.org/10.1134/S154747712303010X