Scaling of deuteron production in ultrarelativistic nucleus-nucleus collisions

Abstract

Deuteron production in S- and Pb-induced collisions at ultrarelativistic energies is studied in a transport model, treating the deuteron production by phase space coalescence. The production rate of deuterons as a function of rapidity, dN d dy , is approximately found to satisfy a simple scaling behavior in terms of the proton and the pion rapidity distributions, dN p dy and dN π dy , namely dN d dy ∼ ( dN p dy ) 2/( dN π dy ) . The scaling is a consequence of the near equality of the freeze-out volumes the nucleons and mesons. Violation of the scaling is attributed to differences between these freeze-out volumes.