Improved effective liquid drop model for α-decay half-lives

Abstract

The effective liquid drop model (ELDM) is improved by introducing an accurate nuclear charge radius formula and an analytic expression of the effective assaulting frequency. Within the improved effective liquid drop model (IMELDM), the α-decay half-lives of 421 nuclei which have been measured in experiment are calculated. It is shown that the accuracy of the IMELDM is improved evidently compared to its predecessor. Meanwhile, by focusing on the superheavy nuclei (SHN), the α-decay half-lives of SHN are investigated within the IMELDM. It is found that the experimental α-decay half-lives of 80 SHN are reproduced well. Then, within the IMELDM the α-decay half-lives of the Z=118–121 isotopes are predicted by inputting the α-decay energies (Qα) extracted from the Weizsäcker-Skyrme-4 (WS4) mass table. At last, the competition between the α-decay and spontaneous fission (SF) of the SHN of the N=178 α-decay chains is studied in detail, which may be useful for searching for the new SHN in future.