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The nuclear equation of state probed by $K^+$ production in heavy ion collisions

C. Fuchs·Amand Faessler·S. El-Basaouny·E. Zabrodin
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Abstract

The dependence of $K^+$ production on the nuclear equation of state is investigated in heavy ion collisions. An increase of the excitation function of $K^+$ multiplicities obtained in heavy ($Au+Au$) over light ($C+C$) systems when going far below threshold which has been observed by the KaoS Collaboration strongly favours a soft equation of state. This observation holds despite of the influence of an in-medium kaon potential predicted by effective chiral models which is necessary to reproduce the experimental $K^+$ yields. Phase space effects are discussed with respect to the $K^+$ excitation function.

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C. Fuchs, Amand Faessler, S. El-Basaouny, E. Zabrodin. 2001-03-15. The nuclear equation of state probed by $K^+$ production in heavy ion collisions. https://doi.org/10.1088/0954-3899%2F28%2F7%2F313

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