Core meets corona: A two-component source to explain Λ and Λ‾ global polarization in semi-central heavy-ion collisions

• Published in: Physics letters. B Vol. 810; p. 135818
• Main Authors: Ayala, Alejandro, Ayala Torres, Marco Alberto, Cuautle, Eleazar, Domínguez, Isabel, Fontaine Sanchez, Marcos Aurelio, Maldonado, Ivonne, Moreno-Barbosa, E., Nieto-Marín, P.A., Rodríguez-Cahuantzi, Mario, Salinas, Jordi, Tejeda-Yeomans, María Elena, Valenzuela-Cázares, L.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 10.11.2020; Elsevier
• ISSN: 0370-2693; 1873-2445
• DOI: 10.1016/j.physletb.2020.135818

We compute the Λ and Λ‾ 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 Λs than Λ‾s are produced in the corona, and this is combined with a smaller number of Λs coming from the core, as compared to those coming from the corona, an amplification effect for the Λ‾ with respect to that of Λ polarization can occur. This amplification becomes more important for lower collision energies and quantitatively accounts for the Λ and Λ‾ polarizations measured by the STAR beam energy scan.