In the Walecka model, the antilambda mass in dense nuclear matter is smaller than its value in free space. This reduces the threshold for antilambda production in dense matter that forms in the compression stage of ultrarelativistic heavy ion collisions. Because of the large number of mesons produced in the collision, the process KM→Λ¯N, where M denotes either a pion or a rho meson, is shown to be important and provides a plausible explanation for the observed enhancement of antilambda yield in recent experiments carried out at CERN SPS with nuclear beams.

• Received 6 May 1992

DOI:https://doi.org/10.1103/PhysRevC.46.1072