Are Multifragment Emission Probabilities Reducible to an Elementary Binary Emission Probability

Experimental intermediate-mass-fragment multiplicity distributions for the E/A=80 and 110 MeV ³⁶Ar + ¹⁹⁷Au reactions are shown to be binomial at all excitation energies. From these distributions, a single binary event probability p can be extracted that has a thermal dependence. Thus, it is inferred that multifragmentation is reducible to a combination of nearly independent emission processes. If sequential decay is assumed, the increase of p with excitation energy implies a contraction of the time scale that is qualitatively consistent with recent fragment-fragment correlation data.