Midrapidity source of intermediate-mass fragments in highly central collisions of Au + Au at 150<i>A</i>MeV

Abstract

Charged particles have been observed in collisions of Au on Au at an incident energy of 150A MeV using a high-granularity detector system covering approximately the forward hemisphere in the center-of-mass system. Highly central collisions have been studied using a double selection criterion which combines large charged-particle multiplicities with small transverse-momentum directivities. In this class of events about one quarter of the total nuclear charge emerges as intermediate-mass fragments with nuclear charges Z&gt;2. These fragments are centered at midrapidity and are produced with large transverse velocities.