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Radial flow of kaon mesons in heavy ion reactions

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

This work investigates the collective motion of kaons in heavy ion reactions at SIS energies (about 1-2 GeV/nucleon). A radial collective flow of $K^+$ mesons is predicted to exist in central Au + Au collisions, which manifests in a characteristic "shoulder-arm" shape of the transverse mass spectrum of the midrapidity $K^+$ mesons. The $K^+$ radial flow arises from the repulsive $K^+$ mean field in nuclear matter. In spite of a strong reabsorption and rescattering the attractive $K^-$ mean field leads as well to a collective radial flow of $K^-$ mesons. The $K^-$ radial flow, however, is different from that of $K^+$ mesons and can be observed by a characteristic "concave" structure of the transverse mass spectrum of the $K^-$ mesons emitted at midrapidity. The kaon radial flows can therefore serve as a novel tool for the investigation of kaon properties in dense nuclear matter.

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Z. S. Wang, Amand Faessler, C. Fuchs, V. S. Uma Maheswari, T. Waindzoch. 1998-04-21. Radial flow of kaon mesons in heavy ion reactions. https://doi.org/10.1103/physrevc.57.3284

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