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arXiv · 2003.13757

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

Alejandro Ayala·Marco Alberto Ayala Torres·Eleazar Cuautle·Isabel Dominguez·Marcos Aurelio Fontaine Sanchez·Ivonne Maldonado·E. Moreno-Barbosa·P. A. Nieto-Marin·M. Rodriguez-Cahuantzi·Jordi Salinas·Maria Elena Tejeda-Yeomans·L. Valenzuela-Cazares
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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.

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Alejandro Ayala, Marco Alberto Ayala Torres, Eleazar Cuautle, Isabel Dominguez, Marcos Aurelio Fontaine Sanchez, Ivonne Maldonado, E. Moreno-Barbosa, P. A. Nieto-Marin, M. Rodriguez-Cahuantzi, Jordi Salinas, Maria Elena Tejeda-Yeomans, L. Valenzuela-Cazares. 2020-09-30. Core meets corona: a two-component source to explain Lambda and anti-Lambda global polarization in semi-central heavy-ion collisions. https://doi.org/10.1016/j.physletb.2020.135818

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