Lambda Lambda interferometry in (K-, K+) and A A reactions

We analyze the invariant mass spectrum of ΛΛ in 12C(K−,K+ΛΛ) reaction at P (K−) = 1.65 GeV/c by using a combined framework of IntraNuclear Cascade (INC) model and the correlation function technique. The observed enhancement at low-invariant masses can be well reproduced with attractive ΛΛ interactions with the scattering length either in the range a = −6 ∼ −4 fm (no bound state) or a = 7 ∼ 12 fm (with bound state) within the present theoretical treatment. We also discuss ΛΛ correlation functions in central relativistic heavy-ion collisions as a possible way to eliminate this discrete ambiguity.