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Longitudinal $\bar Λ_0$ polarization in heavy ion collisions as a probe for QGP formation

G. Herrera·J. Magnin·L. M. Montaño
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Abstract

We present an analysis of the longitudinal $\bar Λ_0$ polarization in ultra-relativistic heavy-ion collisions. The polarization of $\bar Λ_0$'s coming from the decay chain $\barΞ\to \barΛ_0+π$ exhibits a very well differentiated behavior depending on the production region of the primordial $\bar Ξ$'s. This effect reflects the different values of the $N_{\bar Ξ}/N_{\bar Λ_0}$ ratio in the QGP region, where nucleon-nucleon interactions take place in a hot and dense environment, and the peripherical region, in which ordinary nucleon-nucleon interactions occur. An increase in the longitudinal $\bar Λ_0$ polarization signals a strangeness enhancement which is thought as a property of the QGP phase.

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G. Herrera, J. Magnin, L. M. Montaño. 2004-11-01. Longitudinal $\bar Λ_0$ polarization in heavy ion collisions as a probe for QGP formation. https://doi.org/10.1140/epjc%2Fs2004-02073-2

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