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arXiv · 1704.02142

Vorticity in the QGP liquid and $Λ$ polarization at the RHIC Beam Energy Scan

Iu. Karpenko·F. Becattini
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Abstract

Polarization of $Λ$ hyperons and their antiparticles is calculated in a 3+1 dimensional viscous hydrodynamic model with initial state from UrQMD hadron/string cascade. We find that, along with recent results from STAR, the mean polarization at fixed centrality decreases as a function of collision energy from 1.5% at $\sqrt{s_{\rm NN}}=7.7$ GeV to 0.2% at $\sqrt{s_{\rm NN}}=200$ GeV. We explore the effects which lead to such collision energy dependence, feed-down corrections and a difference between $Λ$ and $\barΛ$.

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Iu. Karpenko, F. Becattini. 2017-04-07. Vorticity in the QGP liquid and $Λ$ polarization at the RHIC Beam Energy Scan. https://doi.org/10.1016/j.nuclphysa.2017.05.057

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