Hadron–hadron correlation and interaction from heavy–ion collisions

We investigate the ΛΛ and K−pK−p intensity correlations in high-energy heavy–ion collisions. First, we examine the dependence of the ΛΛ correlation on the ΛΛ interaction and the ΛΛ pair purity probability λ. For small λ, the correlation function needs to be suppressed by the ΛΛ interaction in order to explain the recently measured ΛΛ correlation data. By comparison, when we adopt the λ   value evaluated from the experimentally measured Σ0/ΛΣ0/Λ ratio, the correlation function needs to be enhanced by the interaction. We demonstrate that these two cases correspond to the two analyses which gave opposite signs of the ΛΛ scattering length. Next, we discuss the K−pK−p correlation function. By using the local K¯N potential which reproduces the kaonic hydrogen data by SIDDHARTA, we obtain the K−pK−p correlation function. We find that the K−pK−p correlation can provide a complementary information to the K−pK−p elastic scattering amplitude.