Abstract
The momentum distribution of Λ0 hyperons produced from the quark-gluon plasma (QGP) in ultra-relativistic heavy-ion collisions is calculated in dependence on their polarization. The momentum distribution of Λ0 hyperons is defined by matrix elements of relativistic quark Wigner operators, which are calculated within the effective quark model with chiral U(3)×U(3) symmetry and the quark-gluon transport theory. We show that the polarization of the Λ0 hyperon depends on the spin of the strange quark that agrees well with the DeGrand-Miettinen model. We show that Λ0 hyperons, produced from the QGP, are fully unpolarized. This means that a detection of unpolarized Λ0 hyperons, produced in ultra-relativistic heavy-ion collisions, should serve as one of the signatures for the existence of the QGP in intermediate states of ultra-relativistic heavy-ion collisions.
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Berdnikov, A.Y., Berdnikov, Y.A., Ivanov, A.N. et al. Polarization of Λ0 hyperons as a signature for the quark-gluon plasma. Acta Phys. Hung. A 22, 139–147 (2005). https://doi.org/10.1556/APH.22.2005.1-2.14
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DOI: https://doi.org/10.1556/APH.22.2005.1-2.14