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arXiv · 2106.09443

Global spin polarization of multistrange hyperons and feed-down effect in heavy-ion collisions

Hui Li·Xiao-Liang Xia·Xu-Guang Huang·Huan Zhong Huang
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Abstract

Global spin polarization of hyperons is an important observable to probe the vorticity of the quark-gluon plasma produced in heavy-ion collisions. We calculate the global polarizations of $Λ$, $Ξ^-$, and $Ω^-$ in Au+Au collisions at energies $\sqrt{s_\text{NN}}=$ 7.7--200 GeV based on a multiphase transport model. Our calculations suggest that their primary global polarizations fulfill $P_{Ω^-}\simeq 5/3P_{Ξ^-}\simeq 5/3P_Λ$. We also estimate the feed-down effect of particle decay on the global polarization. With the feed-down effect taken into account, the global polarizations of $Λ$ and $Ξ^-$ are clearly separated, and the final global polarizations are in the ordering: $P_{Ω^-}>P_{Ξ^-}>P_Λ$. Such a relation can be tested in experiments, which will provide us more information about the global polarization mechanism.

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Hui Li, Xiao-Liang Xia, Xu-Guang Huang, Huan Zhong Huang. 2022-01-17. Global spin polarization of multistrange hyperons and feed-down effect in heavy-ion collisions. https://doi.org/10.1016/j.physletb.2022.136971

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