cross section for a production of a given evaporation residue in a heavy ion reaction: one can figure out whether neutron or alpha emission wins a competition with fission at each stage of the deexcitation of a compound nucleus. Moreover, one can try to understand the experimentally established, intriguing growth of the total cross sections around Z=118; for its correlation with $B_f$, see e.g. Fig. 6 and the related discussion in [@O1]. On the other hand, the prediction of the spontaneous or low energy (i.e. from a weakly excited state) fission rates, governed by the regime of the collective quantum tunneling, requires an additional knowledge of the barrier shape and mass parameters.

A non-observable status of the fission barrier, again in analogy to that of the activation energy in chemistry, is reflected in its possible dependence on a reaction type and/or the excitation energy (effective temperature) range. This leads to some uncertainty in calculations of fission barriers. In particular, it is not clear whether intrinsic configurations should be conserved along the level crossings, which increases $B_f$, or the adiabatic state should be followed. This is especially relevant for odd-$A$ and odd-odd nuclei, in which sharp crossings of levels occupied by 