Phase Coexistence in Multifragmentation?

The charge ( Z) distributions from intermediate energy heavy-ion reactions depend upon the multiplicity n of intermediate mass fragments through a factor of the form e^-cnZ. Experimentally c starts from zero at low values of the transverse energy Eₜ and reaches a saturation value at high Eₜ. In a liquid-gas phase diagram c0ex0ex=0ex0ex0 for the saturated vapor, while $c>0$ for the unsaturated vapor. It is suggested that in the c≈0 regime the source evaporates down to a sizable remnant, while for $c>0$ the source vaporizes completely. Percolation of finite systems and nuclear evaporation portray a behavior similar to that observed experimentally.