Predictions of α decay half-lives for even–even superheavy nuclei with 104 ≤ Z ≤ 128 based on two-potential approach within cluster-formation model

In this work, we systematically study the [Formula: see text] decay half-lives of 170 even–even nuclei with [Formula: see text] within the two-potential approach while the [Formula: see text] decay preformation factor [Formula: see text] is obtained by the cluster-formation model. The calculated results can well reproduce the experimental data. In addition, we extend this model to predict the [Formula: see text] decay half-lives of 64 even–even nuclei with [Formula: see text] whose [Formula: see text] decay is energetically allowed or observed but not yet quantified. For comparison, the two famous models i.e., SemFIS proposed by Poenaru et al. [Europhys. Lett. 77 (2007) 62001] and UDL proposed by Qi et al. [Phys. Rev. Lett. 103 (2009) 072501] are used. The predicted results of these models are basically consistent. At the same time, through analyzing the changing trend of [Formula: see text] decay energy [Formula: see text] of [Formula: see text] and 128 isotopes nuclei with the increasing of neutron number N and that of [Formula: see text] decay preformation factor [Formula: see text] of those isotopes even–even nuclei with the increasing of neutron number N, [Formula: see text] may be a new neutron magic number.

Improvement in a phenomenological formula for ground state binding energies

The phenomenological formula for ground state binding energy derived earlier [G. Gangopadhyay, Int. J. Mod. Phys. E 20 (2011) 179] has been modified. The parameters have been obtained by fitting the latest available tabulation of experimental values. The major modifications include a new term for pairing and introduction of a new neutron magic number at N = 160. The new formula reduced the root mean square deviation to 363[Formula: see text]keV, a substantial improvement over the previous version of the formula.

ALPHA ACCOMPANIED TERNARY FISSION OF SUPERHEAVY NUCLEI

Potential energy surfaces corresponding to the alpha accompanied ternary fragmentation in superheavy mass region have been investigated. The lowest value of potential energy is found for the configuration having alpha particle in between other two fragments. The position of deepest valleys in the potential energy surface indicates the most probable tri-partition of a given nucleus. The isotopic effect on the variation of the deepest valley has also been investigated. For the isotopic chain of Z = 114, the minimum is found at 140 Ce + 4 He + 136 Xe , suggesting this to be the most probable tri-partition. Similar possible configurations have been studied for Z = 116, 118 and 120 and the presence of proton/neutron magic number has been found in all the most probable combinations for alpha accompanied ternary fission.