Multifragment disintegrations, measured for central Au + Au collisions at E/A = 35M eV , are analyzed with the Statistical Multifragmentation Model. Charge distributions, mean fragment energies, and two-fragment correlation functions are well reproduced by the statistical breakup of a large, diluted and thermalized system slightly above the multifragmentation threshold.

The relationship between observed intermediate mass fragment and total charged particle multiplicities has been measured for Kr + Au collisions at energies between E/A = 35 and 400 MeV. Pragment multiplicities are greatest for central or near-central collisions. For these collisions, fragment production increases up to E/A-100 MeV, and then decreases at higher energies.

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The fragmentation of EIA =40 MeV Ne projectiles into exit channels containing only p, d, t, He, e, He, Li, and Li fragments has been investigated. Relative shifts between the average longitudinal velocity of each fragment type were measured with ' Sn and ' Au targets. A post-breakup Coulomb acceleration component of these shifts was isolated. Its magnitude indicates that the projectile broke up while in near contact with the target. On the other hand, correlations between projectile fragments indicate that a significant fraction of these fragments are produced by the sequential decay of longand short-lived unstable intermediates. A fully sequential decay process, although consistent with the experimental relative angle distributions, fails to reproduce the correlation function. Thus, a picture emerges of a prompt breakup step producing stable and unstable particles with the subsequent decay of the latter extending over a long time period.