Empirical systematics of spontaneous fission half-lives of heavy and superheavy nuclei

A new phenomenological approach is presented for predicting the spontaneous fission half-lives of actinides and superheavy nuclei. A linear correlation is found between the decimal logarithm of the spontaneous fission half-lives log₁₀T1/2SF and the energy release Q_α of alpha decay for nuclei with the same neutron excess N-Z and atomic numbers in the range 90≤Z≤102. This correlation allows us to propose a semiempirical formula for predicting the spontaneous fission half-lives of even-even nuclei, taking into account both the Q_α and N-Z. The proposed formula is further extended to predict half-lives for odd-A, odd-odd nuclei, and nuclei with Z≥103. A detailed comparison of the predicted half-lives calculated using the microscopic-macroscopic and self-consistent microscopic models and the new semiempirical formula is given. The competition between alpha decay and spontaneous fission is analyzed. The existence of a fundamental relationship between spontaneous fission and alpha-decay processes is discussed.