Global hyperon polarization and effects of decay feeddown

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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.