Fragment yields and phase coexistence in nuclear collisions

It is shown that the apparent power-law behavior of the fragment yields obtained in high-energy proton-nucleus and nucleus-nucleus collisions can be understood in terms of the coexistence of liquid and vapor phases of nulcear matter. The fragment yields are computed by calculating the disassembly of the liquid and vapor sources microcanonically. Good agreement with data is obtained for a wide range of breakup densities. (orig.)