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arXiv · 2509.00796

In-plane transverse polarization in heavy-ion collisions

Anum Arslan·Wen-Bo Dong·Charles Gale·Sangyong Jeon·Qun Wang·Xiang-Yu Wu
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Abstract

We give an analytical expression for the in-plane polarization $P^{x}$, in heavy-ion collisions that has, to our knowledge, not been measured in heavy-ion collision experiments. We also carry out a numerical study of $P^{x}$ using a hydrodynamic model simulation as a cross-check for the analytical formula. It is found that if the temperature-gradient contribution is neglected the simulation result for $P^{x}$ qualitatively agrees with the analytical one. The prediction of $P^{x}$ can be tested in experiments and will contribute to provide a complete and consistent picture of spin phenomena in heavy-ion collisions.

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Anum Arslan, Wen-Bo Dong, Charles Gale, Sangyong Jeon, Qun Wang, Xiang-Yu Wu. 2025-08-31. In-plane transverse polarization in heavy-ion collisions. https://arxiv.org/abs/2509.00796

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