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Origin of subthreshold K^+ production in heavy ion collisions

C. Fuchs·Z. Wang·L. Sehn·Amand Faessler·V. S. Uma Maheswari·D. S. Kosov
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Abstract

We investigate the origin of subthreshold $K^+$ production in heavy ion collisions at intermediate energies. In particular we study the influence of the pion induced $K^+$ creation processes. We find that this channel shows a strong dependence on the size of the system, i.e., the number of participating nucleons as well as on the incident energy of the reaction. In an energy region between 1--2 GeV/nucleon the pion induced processes essentially contribute to the total yield and can even become dominant in reactions with a large number of participating nucleons. Thus we are able to reproduce recent measurements of the KaoS Collaboration for 1 GeV/nucleon Au on Au reactions adopting a realistic momentum dependent nuclear mean field.

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C. Fuchs, Z. Wang, L. Sehn, Amand Faessler, V. S. Uma Maheswari, D. S. Kosov. 1997-06-26. Origin of subthreshold K^+ production in heavy ion collisions. https://doi.org/10.1103/physrevc.56.r606

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