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Lambda collective flow in heavy ion reactions

Z. S. Wang·Amand Faessler·C. Fuchs·T. Waindzoch
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Abstract

Collective flow of Lambda hyperons in heavy ion reactions at SIS energies is investigated. It is found that a $Λ$ mean field constructed on the basis of the quark model leads to a good description of the experimental data of the in-plane transverse flow of $Λ$'s. The attractive mean field can also give rise to an additional "virtual" $Λ$ radial flow directed inwards, which is reflected by a "concave" structure of the transverse mass spectrum of the $Λ$ hyperons emitted at midrapidity. The $Λ$ radial flow is found to exhibit a strong mass dependence: The flow is visible in the Ni+Ni system, but is strongly reduced in the system of Au on Au.

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Z. S. Wang, Amand Faessler, C. Fuchs, T. Waindzoch. 1998-11-25. Lambda collective flow in heavy ion reactions. https://doi.org/10.1016/s0375-9474(98)00605-8

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