Systematic Study on Alpha Decay Half-Lives of Superheavy Nuclei

The a-decay half-lives of a set of superheavy nuclear isotope chain from Z=105 to 120 have beenanalyzed systematically within the WKB method,and some nuclear structure features are found.The decay barriershave been determined in the quasi-molecular shape path within the Generalized Liquid Drop Model （GLDM） includingthe proximity effects between nucleons in a neck and the mass and charge asymmetry.The results are in reasonableagreement with the published experimental data for the alpha decay half-lives of isotopes of charge 112,114,and 116,ofthe dement;118 and of some decay products.A comparison of present calculations with the results by the DDM3Yeffective interaction and by the Viola-Seaborg-Sobiczewski （VSS） formulae is also made.The experimental a decay halflives all stand in between the GLDM calculations and VSS formula results.This demonstrates the possibility of thesemodels to provide reasonable estimates for the half-lives of nuclear decays by a emissions for the domain of SHN.Thehalf-lives of these new nuclei are thus well tested from the reasonable consistence of the macroscopic,the microscopic,theempirical formulae and the experimental data.This also shows that the present data of SHN themselves are consistent.It could suggest that the present experimental claims on the existence of new elements Z=110～118 are reliable.It is expected that greater deviations of a few SHN between the data and the modal may be eliminated by furtherimprovements on the precision of the measurements.