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Probing the nuclear equation of state by $K^+$ production in heavy ion collisions

C. Fuchs·Amand Faessler·E. Zabrodin·Yu-Ming Zheng
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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.

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C. Fuchs, Amand Faessler, E. Zabrodin, Yu-Ming Zheng. 2001-01-17. Probing the nuclear equation of state by $K^+$ production in heavy ion collisions. https://doi.org/10.1103/physrevlett.86.1974

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