Determination of α preformation for heavy nuclei

The alpha preformation factor and the penetration probability have been analyzed for heavy even-even nuclei in the frame of double folding model using the experimental released energies and alpha decay half-lives. The alpha preformation factors are compared with Po, Rn, Ra isotopes as well as Cm, Cf, Fm, No, Rf isotopes, respectively. It is shown that the alpha preformation factor is variable and the shell effects play an important role in the alpha preformation. The closer the nucleon number to magic number, the more difficult the alpha formation in the parent nucleus is. The preformation factor can supply the information of nuclear structure and the penetration probability determines mainly a decay half-life. (C) 2009 Elsevier B.V. All rights reserved.