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arXiv · 2507.04989

Spin alignment of vector mesons in heavy-ion collision

Xin-Li Sheng·Qun Wang
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Abstract

We give a brief review on the spin alignment induced by the strong field and the shear-stress tensor. In experiments, a significant positive deviation from 1/3 is observed for the $\phi$ meson, which can be explained by the anisotropy of the strong field fluctuation in the meson's rest frame, while the anisotropy is mainly a consequence of the motion of meson relative to the quark-gluon plasma. On the other hand, the shear-induced spin alignment is of the order $10^{-4}\sim10^{-5}$ if the magnitude of thermal shear tensor is $10^{-2}$.

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Xin-Li Sheng, Qun Wang. 2025-07-07. Spin alignment of vector mesons in heavy-ion collision. https://arxiv.org/abs/2507.04989

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