Using charged-particle-exclusive measurements of $\mathrm{Au}+\mathrm{Au}$ collisions in the LBL Bevalac's EOS time projection chamber, we investigate momentum-space densities of fragments up to ${}^4\mathrm{He}$ as a function of fragment transverse momentum, azimuth relative to the reaction plane, rapidity, multiplicity, and beam energy. Most features of these densities above a transverse momentum threshold are consistent with momentum-space coalescence, and, in particular, the increase in sideward flow with fragment mass is generally well described by a momentum-space power law.

• Received 29 August 1994

DOI:https://doi.org/10.1103/PhysRevLett.74.2646