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arXiv · 1610.04717

Study of Lambda polarization in relativistic nuclear collisions at sqrt{s}_NN = 7.7-200 GeV

Iu. Karpenko·F. Becattini
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Abstract

We present a calculation of the global polarization of Lambda hyperons in relativistic Au-Au collisions at RHIC Beam Energy Scan range sqrt{s}_NN = 7.7 - 200 GeV with a 3+1 dimensional cascade + viscous hydro + cascade model, UrQMD+vHLLE. Within this model, the mean polarization of Lambda in the out-of-plane direction is predicted to decrease rapidly with collision energy from a top value of about 2% at the lowest energy examined. We explore the connection between the polarization signal and thermal vorticity and estimate the feed-down contribution to Lambda polarization due to the decay of higher mass hyperons.

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Iu. Karpenko, F. Becattini. 2017-04-06. Study of Lambda polarization in relativistic nuclear collisions at sqrt{s}_NN = 7.7-200 GeV. https://doi.org/10.1140/epjc%2Fs10052-017-4765-1

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