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arXiv · 2509.00377

Local spin polarization of $\Lambda$ hyperons and its interaction corrections

Cong Yi·Shuo Fang·Dong-Lin Wang·Shi Pu
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Abstract

We have computed the second Fourier sine coefficient of the longitudinal spin polarization, $\langle P_{z} \sin 2(\phi_{p} - \Psi_{2}) \rangle$, as a function of multiplicity or centrality in Au+Au collisions at $\sqrt{s_{NN}} = 200$ GeV and in $p$+Pb collisions at $\sqrt{s_{NN}} = 8.16$ TeV using the CLVisc hydrodynamic framework. The numerical results successfully describe the data in Au+Au collisions. However, understanding the data in $p$+Pb collisions remains a puzzle. Additionally, we have reported some recent developments in quantum kinetic theory and spin hydrodynamics.

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Cong Yi, Shuo Fang, Dong-Lin Wang, Shi Pu. 2025-08-30. Local spin polarization of $\Lambda$ hyperons and its interaction corrections. https://arxiv.org/abs/2509.00377

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