Within the framework of a previously developed transition-state theory
for nuclear multifragmentation, we study the effect of pre-transition
radiation of nucleons on the partial widths for breakup into specifie
d multifragment channels. Typically, a considerable portion of the mas
s and energy of the source is radiated during the evolution of the sys
tem from a spherical compound nucleus towards the conditional saddle c
onfiguration, thus causing a significant reduction of the multifragmen
tation width.