Directed and elliptic flow of light nuclei and hypernuclei in Au+Au collisions at $\sqrt{s_\mathrm{NN}}=3$ GeV: Coalescence vs. Statistical Fragmentation

Tom Reichert; Manjunath Omana Kuttan; Apiwit Kittiratpattana; Nihal Buyukcizmeci; Alexander Botvina; Jan Steinheimer; Marcus Bleicher

arXiv · 2504.17389

Directed and elliptic flow of light nuclei and hypernuclei in Au+Au collisions at $\sqrt{s_\mathrm{NN}}=3$ GeV: Coalescence vs. Statistical Fragmentation

Tom Reichert·Manjunath Omana Kuttan·Apiwit Kittiratpattana·Nihal Buyukcizmeci·Alexander Botvina·Jan Steinheimer·Marcus Bleicher

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Abstract

The harmonic flow coefficients of light nuclei and hypernuclei in Au+Au collisions at $\sqrt{s_\mathrm{NN}}=3$ GeV are investigated using the Ultra-relativistic Quantum Molecular Dynamics transport model. For the Equation-of-State we employ a density and momentum dependent potential from the Chiral-Mean-Field model. Light nuclei and hypernuclei production is described at kinetic freeze-out via a coalescence mechanism or with a statistical multi-fragmentation calculation. The directed flow $v_1$ of p, d, t, $^3$He, $^4$He as well as the $\Lambda$, $^3_\Lambda$H and $^4_\Lambda$H is shown to approximately scale with mass number $A$ of the light cluster in both calculations. This is in agreement with the experimental results for the directed flow measured by STAR. Predictions for the directed and elliptic flow of (hyper)nuclei at further RHIC-FXT and FAIR energies show that the scaling properties should improve as the beam energy is increased.

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Tom Reichert, Manjunath Omana Kuttan, Apiwit Kittiratpattana, Nihal Buyukcizmeci, Alexander Botvina, Jan Steinheimer, Marcus Bleicher. 2025-04-24. Directed and elliptic flow of light nuclei and hypernuclei in Au+Au collisions at $\sqrt{s_\mathrm{NN}}=3$ GeV: Coalescence vs. Statistical Fragmentation. https://arxiv.org/abs/2504.17389

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