No abstract

The disappearance of collective flow in nucleus-nucleus collisions occurs at an incident energy (^bai) where the attraxitive scattering dominant at low energies balances the repulsive scattering dominant at high energies. We have performed the first systematic study of the entrance-channel mass dependence of the disappearance of flow and hence -Ebai-The new data presented for the C-j-C, Ne-hAl, Ar+Sc, and Kr+Nb systems show that JE^bai scales as A~^^^ where A is the mass of the combined system. Boltzmann-Uehling-Uehlenbeck model calculations show trends which are in qualitative agreement with these new results.