Are Multifragment Emission Probabilities Reducible to an Elementary Binary Emission Probability

Abstract

Experimental intermediate-mass-fragment multiplicity distributions for the $\frac{E}{A}=80 \mathrm{and} 110$ MeV $^{36}\mathrm{Ar}$ + $^{197}\mathrm{Au}$ 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.