K^± production in heavy-ion collisions at √s _NN = 3 - 5 GeV

We present the results of K^± production by using a schematic model that takes into account the nuclear equation-of-state effect and the in-medium modification of the K^± masses in hot, dense nuclear matter at √S_NN = 3 - 5 GeV. Within the framework of this model, the enhancement of the K⁺ production by the soft equation-of-state overcomes the suppression by the weak repulsive K⁺N potential in heavy-ion collisions. The estimated yield ratios of K ⁺/K^- agree with the measurements at the Alternating Gradient Synchrotron (AGS) if we assume the freeze-out baryonic density to be about twice the ground-state nuclear-matter density. The model can also reproduce the absolute total multiplicities of K^± in central Au + Au collisions with a similar baryonic density. More differential analysis of K^± production at this beam energy range will be explored in detail in the future SIS300 heavy-ion synchrotron at Gesellschaft für Schwerionenforschung (GSI), Darmstadt, Germany.