Femtoscopic study of the Λα interaction

We examine the Λ-⁴He (α) momentum correlation in high-energy collisions to elucidate the interaction between Lambdas (Λ) and nucleons (N). We compare phenomenological Λα potentials with different strengths at short range. In addition to the conventional Gaussian-type potentials, we construct the Λα potentials by substituting the nucleon density distribution in α into the Skyrme-type Λ potentials. We find that the dependence on the employed potential models is visible in the correlation functions from a small-size source. This indicates that the Λα momentum correlation could constrain the property of the Λ N interaction at high densities, which is expected to play an essential role in dense nuclear matter. Also, we verify that the Lednicky-Lyuboshits formula can yield erroneous results for a small-size source with a potential which has a large interaction range, like the Λα system.