Core meets corona: A two-component source to explain Λ and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si1.svg"><mml:mover accent="true"><mml:mrow><mml:mi mathvariant="normal">Λ</mml:mi></mml:mrow><mml:mo>‾</mml:mo></mml:mover></mml:math> global polarization in semi-central heavy-ion collisions
Alejandro Ayala, M. Ayala-Torres, Eleazar Cuautle, I. Domínguez Jiménez, Marcos Aurelio Fontaine Sánchez, I. Maldonado Cervantes, E. Moreno, P. A. Nieto-Marín, M. Rodríguez Cahuantzi, Jordi Salinas, María Elena Tejeda-Yeomans, Luis Valenzuela-Cázares
Abstract
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.