Effects of diabaticity on fusion of heavy nuclei in the dinuclear model ...

The similarity <strong>of</strong> the potential energy U as a function <strong>of</strong> η at the touching configuration <strong>of</strong> the
nuclei calculated within different approaches can indicate the stability <strong>of</strong> the results obtained
in the DNS model.
Using a small overlap <strong>of</strong> the DNS nuclei, the value <strong>of</strong> U is calculated as the sum <strong>of</strong> asymptotic
binding energies <strong>of</strong> the nuclei and the nucleus-nucleus potential [34, 65] in the phenomenological
treatment. Since the DNS nuclei retain their individual properties, in this approach the shell
effects enter U through the binding energies <strong>of</strong> the two nuclei.
In the microscopical consideration, the DNS potential energy as a function <strong>of</strong> η can be
calculated within the adiabatic TCSM using the Strutinsky method. Contrary to the phenom-
enological approach, in the TCSM-method we do not need the calculation <strong>of</strong> the nucleus-nucleus
interaction. There is an alternative microscopical method where the energy <strong>of</strong> the DNS as a
function <strong>of</strong> η is calculated using the rate <strong>of</strong> probability <strong>of</strong> nucleon transfer between the DNS
nuclei. In this method, which we call ”alternative microscopical method” to distinguish it from
the TCSM-method, the energy contains not only the potential energy, but the contribution from
the kinetic energy. Therefore, this driving potential could deviate from the driving potentials
calculated phenomenologically and within the TCSM.
In Sect. 4-1, methods <strong>of</strong> calculation <strong>of</strong> the driving potential in the phenomenological ap-
proach, within the TCSM and in the alternative microscopical approach are presented. The
isotopic dependence <strong>of</strong> the phenomenological driving potential was analysed in [67]. In Sect. 4-
2, we check whether this dependence is the same for the driving potential calculated within the
TCSM. The isotopic dependence <strong>of</strong> the fusion barrier in mass asymmetry is studied. The effect
<strong>of</strong> the deformation <strong>of</strong> the DNS nuclei on the potential energy is demonstrated.
4.1 Methods <strong>of</strong> calculation <strong>of</strong> the driving potential
4.1.1 Phenomenological method
The phenomenological driving potential is calculated as in [34, 65]
U(R, η, ηZ) =B1 + B2 + V (R, η, ηZ) − B12, (4.1)
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