Correlations between slow and fast fragments in relativistic nuclear collisions

Heavy low-energy fragments with Z≥4 have been measured in relativistic nuclear collisions, using a large area ionization chamber telescope. For all events, correlated slow fragments were looked for in five solid state counters and correlated fragments ($E>25$ MeV/u) were measured in 80 scintillators coupled to photomultipliers. Fragment spectra were taken in the energy range of 5-150 MeV Eₜₒₜ. p_∥ was extracted for fissionlike events. Other nonbinary fragments showed an in-plane correlation with fast charged particles. Lighter particles (4≤Z≤12) were found to be associated with a high charged-particle multiplicity. Conflicts with previous views on high-energy proton-nucleus data are pointed out and a qualitative comparison to hydrodynamical effects is tried.NUCLEAR REACTIONS U(p, HF) 1.05 GeV; U(p, HF), Au(p, HF) 2.1 GeV; U(⁴He, X), Au(⁴He, X) 400 MeV/u, 1.05 GeV/u; Ag(⁴He, X) 1.05 GeV/u; U(²⁰Ne, X), Au(²⁰Ne, X), Ag(²⁰Ne, X) 400 MeV/u. Measured: σ(E, θ), associated charged-particle multiplicity M(X, θ, φ); d²ΩdΩ₁dΩ₂; X=BetoMg, $12 26$; Fission fragments.