α preformation and penetration probability for heavy nuclei

The α preformation factor and penetration probability have been analyzed for even-even nuclei of Po,Rn,Ra using experimental released energies and α decay half-lives in the frame of the double folding model.It is shown that N = 126 is a neutron magic number from α preformation and shell effects play an important role in α preformation.The closer the nucleon number is to the magic number,the more difficult α formation in the parent nucleus is.The preformation factor can supply information on the nuclear structure and the penetration probability mainly determines α decay half-life.