The influence of KN potential on the production of kaon mesons in heavy-ion collisions at intermediate energies

Abstract

The kaon meson produced in heavy ion collisions can be taken as a useful probe for investigating the properties of dense nuclear matter. With the help of transport model simulations, it can be used to extract the information of the equation of state of nuclear matter. Within the newly updated version of the ultrarelativistic quantum molecular dynamics (UrQMD) model, the kaon-nucleon (KN) potential is further taken into account and its influence on both the yield and the directed and elliptic flows of kaon mesons produced in Au+Au collisions at intermediate energies ($E_{\rm lab}$=0.6-2.0 GeV$/$nucleon) is investigated. It is found that the experimental data of flows can be better described with the consideration of the KN potential, and it is further found that the K$^0$/K$^+$ yield ratio is affected by the density dependence of the nuclear symmetry energy. The K$^0$/K$^+$ ratio calculated with a soft symmetry energy is larger than that with a stiff one, and the sensitivity to the density dependence of the nuclear symmetry energy at lower beam energy becomes larger. At the low energy such as 0.8 GeV$/$nucleon, the K$^0$/K$^+$ ratio is more sensitive to the stiffness of nuclear symmetry energy than the $\uppi^-$/$\uppi^+$ ratio is.