Longitudinal Λ̄ 0 polarization in heavy ion collisions as a probe for QGP formation
نویسندگان
چکیده
Longitudinal ¯ Λ 0 polarization in heavy ion collisions as a probe for QGP formation. Abstract We present an analysis of the longitudinal ¯ Λ 0 polarization in ultra-relativistic heavy-ion collisions. The polarization of ¯ Λ 0 's coming from the decay chain ¯ Ξ → ¯ Λ 0 + π exhibits a very well differentiated behavior depending on the production region of the primordial ¯ Ξ's. This effect reflects the different values of the N¯ Ξ /N¯ 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 ¯ Λ 0 polarization signals a strangeness enhancement which is thought as a property of the QGP phase.
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