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Lambda^0 polarization as a probe for production of deconfined matter in ultra-relativistic heavy-ion collisions

Alejandro Ayala·Eleazar Cuautle·Gerardo Herrera·Luis Manuel Montaño
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Abstract

We study the polarization change of Lambda^0's produced in ultra-relativistic heavy-ion collisions with respect to the polarization observed in proton-proton collisions as a signal for the formation of a Quark-Gluon Plasma (QGP). Assuming that, when the density of participants in the collision is larger than the critical density for QGP formation, the Lambda^0 production mechanism changes from recombination type processes to the coalescence of free valence quarks, we find that the Lambda^0 polarization depends on the relative contribution of each process to the total number of Lambda^0's produced in the collision. To describe the polarization of Lambda^0's in nuclear collisions for densities below the critical density for the QGP formation, we use the DeGrand-Miettinen model corrected for the effects introduced by multiple scattering of the produced Lambda^0 within the nuclear environment.

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Alejandro Ayala, Eleazar Cuautle, Gerardo Herrera, Luis Manuel Montaño. 2001-10-10. Lambda^0 polarization as a probe for production of deconfined matter in ultra-relativistic heavy-ion collisions. https://doi.org/10.1103/physrevc.65.024902

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