Core meets corona: a two-component source to explain Lambda and anti-Lambda global polarization in semi-central heavy-ion collisions

Abstract

We compute the Lambda and anti-Lambda global polarization in semi-central heavy-ion collisions modeling the source as consisting of a high-density core and a less dense corona. We show that when more Lambdas than anti-Lambdas are produced in the corona, and this is combined with a smaller number of Lambdas coming from the core, as compared to those coming from the corona, an amplification effect for the anti-Lambda with respect to that of Lambda polarization can occur. This amplification becomes more important for lower collision energies and quantitatively accounts for the Lambda and anti-Lambda polarizations measured by the STAR beam energy scan.

6 pages, 5 figures. Version to appear in Phys. Lett. B

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Cited by in corpus (10)

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• Rise and fall of $\Lambda$ and $\bar{\Lambda }$ global polarization in semi-central heavy-ion collisions at HADES, NICA and RHIC energies from the core-corona model
• Fermion propagator in a rotating environment
• Impact of strong magnetic field, baryon chemical potential, and medium anisotropy on polarization and spin alignment of hadrons
• Hyperon global polarization in heavy-ion collisions at NICA energies. Feed-down effects and the role of ${\Sigma }^0$ hyperons
• Investigate the $\Lambda$ and $\bar{\Lambda }$ polarization splitting effect with combined mechanisms
• Two-component source to explain $\Lambda$ and $\bar{\Lambda }$ global polarization in non-central heavy-ion collisions