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arXiv · 1611.08136

Vorticity in the QGP liquid and hyperon polarization at the RHIC BES energies

Iu. Karpenko·F. Becattini
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Abstract

We calculate the polarization of $\Lambda$ hyperons in Au-Au collisions at RHIC Beam Energy Scan range $\sqrt{s_{\rm NN}}=7.7, \dots, 200$ GeV in a state-of-the-art 3+1 dimensional cascade + viscous hydro model vHLLE+UrQMD. We find that the polarization of $\Lambda$ in the out-of-plane direction decreases substantially with collision energy. We explore the connection between the polarization signal and thermal vorticity and discuss the feed-down and hadronic rescattering effects on the mean polarization of all produced $\Lambda$ hyperons.

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Iu. Karpenko, F. Becattini. 2016-11-24. Vorticity in the QGP liquid and hyperon polarization at the RHIC BES energies. https://doi.org/10.1088/1742-6596/779/1/012068

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