Strangeness by Thermal Model Simulation at RHIC

The local temperature effect on strangeness enhancement in relativistic heavy ion collisions is discussed in the framework of the thermal model in which the K+/h+ ratio becomes smaller with increasing freeze-out temperature. Considering that most strangeness particles of final-state particles are from the kaon meson, the temperature effect may play a role in strangeness production in hot dense matter where a slightly different temperature distribution in different areas could be produced by jet energy loss. This phenomenon is predicted by thermal model calculation at RHIC energy. The Ξ−/ ratio in central Au+Au collisions at 200 GeV from the thermal model depends on the freeze-out temperature obviously when γS is different. It should be one of the reasons why strangeness enhancements of Ξ and are different though they include two strange quarks. These results indicate that thermodynamics is an important factor for strangeness production and the strangeness enhancement phenomenon.