Does nuclear fragmentation explore the gas-liquid phase transition of nuclear matter

The phase space of channels is calculated into which a nucleus may decay after being hit by a proton with Esub(p) > 10 GeV. Special care is given to the finite size of the system and to the Coulomb interaction between the fragments. Both effects are shown to be of crucial and dominant importance. At a temperature of 4-5 MeV the target decays into many fragments simultaneously. The mass yields is reproduced by the model over the entire mass range. Monte Carlo simulations show that also the energy spectra may realistically be reproduced and the slope parameter (the apparent temperature) Tsub(app) is --2 times larger than the true temperature. This is due to considerable fluctuations in the number of fragments and in their mutual Coulomb-interaction. The gasliquid phase transition in nuclear matter is dramatically modified by these finite size and strong Coulomb effects. Some general features of this transition are discussed. (author)