ROLE OF THE COULOMB INTERACTION IN THE FLOW AND THE AZIMUTHAL DISTRIBUTION OF KAONS FROM HEAVY-ION REACTIONS

Coulomb final-state interaction of positive charged kaons in heavy ion reactions and its impact on the kaon transverse flow and the kaon azi muthal distribution are investigated within the framework of QMD (quan tum molecular dynamics) model. The Coulomb interaction is found to ten d to draw the flow of kaons away from that of nucleons and lead to a m ore isotropic azimuthal distribution of kaons in the target rapidity r egion. The recent FOPI data have been analyzed by taking into account both the Coulomb interaction and a kaon in-medium potential of the str ong interaction. Although the effect of the kaon Coulomb potential on the kaon flow and azimuthal distribution is much smaller than that of the strong potential, it is found to be visible, and therefore, should be taken into account if one wants to extract unambiguous information about the kaon strong potential in nuclear matter from the kaon flow and azimuthal distribution data. (C) 1998 Elsevier Science B.V.