VELOCITY CORRELATIONS OF INTERMEDIATE-MASS FRAGMENTS PRODUCED IN CENTRAL COLLISIONS OF AU+AU AT E=150A MEV

Velocity correlations of intermediate mass fragments (IMFs), produced in central collisions of Au + Au at 150 A MeV beam energy, are extract ed from measurements with the FOPI (phase I) detector system at SIS in GSI Darmstadt. The IMF correlation function for semicentral events is found to be affected by the directed sideward flow. When rotating the events into a unique reaction plane an enhancement of correlations, r esulting from event mixing effects, vanishes. Selecting violent collis ions with a high degree of azimuthal symmetry the correlation function appears nearly independent of additional event or single particle gat e conditions. The comparison of the data with a Coulomb dominated fina l-state interaction model points to an expanding and multifragmenting source with radius R is similar to 14 fm.