Multifragmentation of spectator matter

摘要

The first microscopic calculation of the spectator fragmentation observed in heavy ion reactions at relativistic energies is presented which reproduces the slope of the kinetic energy spectra of the fragments as well as their multiplicity, both measured by the ALADIN collaboration. It is shown that both observables are dominated by dynamical processes and that the system does not pass a state of thermal equilibrium. These findings question the recent conjecture that in these collisions a phase transition of first order, similar to that between water and vapor, can be observed. (K.A.). 12 refs. (Atomindex citation 29:006805)