  In this paper, the distribution of mass and kinetic energy in the cold region
of the thermal neutron induced fission of U 233, U 235 and Pu 239,
respectively, is interpreted in terms of nucleon pair-breaking and the Coulomb
interaction energy between complementary fragments (Coulomb effect). In order
to avoid the erosive consequences of neutron emission, one studies the cold
fission regions, corresponding to total kinetic energy (TE) close to the
maximum available energy of the reaction (Q). Contrary to expected, in cold
fission is not observed high odd-even effect in mass number distribution.
Nevertheless, the measured values are compatible with higher odd-even effects
on proton or neutron number distribution, respectively. In addition, in cold
fission, the minimal total excitation energy (X) is correlated with the Coulomb
energy excess, which is defined as the difference between C (the electrostatic
interaction energy between complementary fragments taken as spherical in
scission configuration) and Q. These Coulomb effects increase with the
asymmetry of the charge fragmentations. In sum, the experimental data on cold
fission suggest that scission configurations explore all the possibilities
permitted by the available energy for fission.
