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arXiv · nucl-ex/0305017

Strangeness from 20 AGeV to 158 AGeV

Volker Friese
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Abstract

New results from the energy scan programme of NA49, in particular kaon production at 30 AGeV and phi production at 40 and 80 AGeV are presented. The K+/pi+ ratio shows a pronounced maximum at 30 AGeV; the kaon slope parameters are constant at SPS energies. Both findings support the scenario of a phase transition at about 30 AGeV beam energy. The phi/pi ratio increases smoothly with beam energy, showing an energy dependence similar to K-/pi-. The measured particle yields can be reproduced by a hadron gas model, with chemical freeze-out parameters on a smooth curve in the T-muB plane. The transverse spectra can be understood as resulting from a rapidly expanding, locally equilibrated source. No evidence for an earlier kinetic decoupling of heavy hyperons is found.

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Volker Friese. 2003-05-20. Strangeness from 20 AGeV to 158 AGeV. https://doi.org/10.1088/0954-3899%2F30%2F1%2F011

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