Dynamical calculations of spontaneous-fission half-lives

Spontaneous-fission half-lives are calculated for the heaviest even-even nuclei (Z=96-110). The penetration of the fission barrier is treated as a one-dimensional problem, in the WKB approximation. The potential energy is calculated as a sum of the Myers-Swiatecki droplet model energy and the shell correction obtained by the Strutinsky method. Quadrupole axial and non-axial deformations and axial deformations of multipolarities three, five and six are considered. The mass tensor (only six components) is calculated in the cranking approximation. All microscopic calculations are based on the modified oscillator single-particle potential. The action integral is minimized by two different variational methods. No free parameters are used. - The calculated half-lives reproduce the experimental values with an accuracy slightly better than two orders (around a factor of 50), on the average. (author)