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arXiv · 2108.04111

Global hyperon polarization and effects of decay feeddown

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

We study the global polarizations of $\Lambda$, $\Xi^-$, and $\Omega^-$ hyperons in noncentral Au+Au collisions at $\sqrt{s_\mathrm{NN}}=$ 7.7-200 GeV. We highlight the importance of effect of decay feeddown to the measured global polarization. With the decay contributions taken into account, the global polarization ordering $P_{\Omega^-} > P_{\Xi^-} > P_\Lambda$ can be naturally explained, which is consistent with the observation recently reported from the STAR experiment from Au+Au collisions at 200 GeV. We also extend our calculations to predict expectations from the RHIC-BES II data.

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Hui Li, Xiao-Liang Xia, Xu-Guang Huang, Huan Zhong Huang. 2021-08-09. Global hyperon polarization and effects of decay feeddown. https://doi.org/10.1051/epjconf/202225911017

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