Binding energies, α-decay energies, and α-decay half-lives for heavy and superheavy nuclei

Combined with the new table of atomic mass evaluation (AME) 2011, the binding energies and alpha-decay energies for heavy and superheavy nuclei are investigated based on the previous studies. First, we use the new data from the AME2011 to check the reliability of the previously proposed formulas. It is found that there is good agreement between the calculated results and new experimental data, showing the good predictive power of the formulas. Then, a new formula with fewer adjustable parameters is presented for binding energies, and it shows better agreement with the available experimental data. However, it is still hard to use it to accurately calculate the alpha-decay energies of superheavy nuclei with N >= 160 and Z >= 106. A new formula of alpha-decay energies is proposed as well, where the shell corrections are better described and the Z = 108 proton shell effect is added. The experimental Q alpha values are reproduced with improved accuracy especially for heavier nuclei. This improvement is of great importance for precise predictions of alpha-decay half-lives for unknown superheavy nuclei. Moreover, the new Q alpha formula and the theoretical FRDM95 and KTUY05 masses are used to determine the Q alpha values of superheavy nuclei with Z = 108-120, and their alpha-decay half-lives are calculated using the generalized density-dependent cluster model (GDDCM). The agreement between theoretical results and known experimental data is discussed, together with the deformed shell effects in the superheavy mass region. (c) 2012 Elsevier B.V. All rights reserved.