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

7-2). In the reactions leading to the nuclei 286 112 and 292 114, the decay <strong>of</strong> the more symmetric
DNS configurations becomes more pronounced. The motion <strong>of</strong> the initial DNS to more asym-
metric configurations (mass asymmetry channel <strong>of</strong> fusion) in the reaction 48 Ca+ 208 Pb is more
favourable than in the reactions 48 Ca+ 238 Uand 48 Ca+ 244 Pu, where the distributions show
similar features for Z 48, around the nuclei 78 Zn and 32 Ge, respectively, for the
light fragment with the corresponding heavy fragment 208 Pb. The height <strong>of</strong> this peak is 6 (3)
times larger than the height <strong>of</strong> the peak in the symmetric mass region in the reaction 48 Ca+ 238 U
( 48 Ca+ 244 Pu). One can see that the results are in good agreement with the available experi-
mental data, which were extracted from Ref.[11]. This experimental mass distribution includes
the quasi-fission events in all angles measured. It should be noted that near the initial DNS
configuration, the quasi-fission events overlapping with the products <strong>of</strong> other reaction channels
(elastic and quasi-elastic peaks) were not taken into account in the experimental data because
they cannot be clearly distinguish. In our calculations we assume that the DNS is formed in
all reactions considered. In general, the formation <strong>of</strong> the DNS also depends on the capture
probability, which is determined by the dynamical aspects <strong>of</strong> the approach stage <strong>of</strong> the reaction
and by the depth <strong>of</strong> the pocket in the nucleus-nucleus interaction potential in the entrance
channel [38].
The excitation energy <strong>of</strong> the initial DNS in all reactions considered is E ∗ =10 MeV and
the lifetime t0 <strong>of</strong> the DNS is about (3 − 4)× 10 −20 s. The initial excitation energy E ∗ can be
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