  The cross section curves for the formation, at the barrier, of trans-target
isotopes of a heavy element by bombardment of a heavy target with various heavy
ions are shown to be similar to the distribution of the neutron number N of a
fission fragment around its most probable value . Moreover the isotopic cross
sections for one-, two- and three- proton transfer products are found to be in
agreement with the Gaussian distribution law of the atomic number Z of a
fission product around its most probable value . This situation suggests that
the law of transfer of nucleons could be the same in fission and in particular
heavy-ion reactions, and that the transfer time could be the same, i.e. of the
order of 0.17 yoctosecond.
