  The understanding of the fusion probability is of particular importance to
reveal the mechanism of producing superheavy elements. We present a microscopic
study of the compound nucleus formation by combining time-dependent density
functional theory, coupled-channels approach, and dynamical diffusion models.
The fusion probability and compound nucleus formation cross sections for
cold-fusion reactions $^{48}$Ca+$^{208}$Pb, $^{50}$Ti+$^{208}$Pb, and
$^{54}$Cr+$^{208}$Pb are investigated and it is found that the deduced capture
barriers, capture cross sections for these reactions are consistent with
experimental data. Above the capture barrier, our calculations reproduce the
measured fusion probability reasonably well. Our studies demonstrate that the
restrictions from the microscopic dynamic theory improve the predictive power
of the coupled-channels and diffusion calculations.
