In the present work considering the contributions of the daughter nuclear charge and the orbital angular momentum taken away by the emitted proton, we propose a two-parameter formula of new Geiger-Nuttall law for proton radioactivity. A set of universal parameters of this law is obtained by fitting 44 experimental data of proton emitters in the ground state and isomeric state. The calculated results can reproduce the experimental data well. For a comparison, the calculations performed using other theoretical methods, such as UDLP proposed by Qi et al. [Phys. Rev. C 85, 011303(R) (2012)], the CPPM-Guo2013 analyzed by our previous work [Deng et al., Eur. Phys. J. A 55, 58 (2019)] and the modified Gamow-like model proposed by us [Chen et al., J. Phys. G: Nucl. Part. Phys. 96, 065107 (2019)] are also included.Meanwhile, we extend this new Geiger-Nuttall law to predict the proton radioactivity half-lives for 51 ≤ Z ≤ 91 nuclei, whose proton radioactivity is energetically allowed or observed but not yet quantified in NUBASE2016.

In present work, we systematically study the α decay half-lives of 170 even-even nuclei with 60 Z 118 within the two-potential approach while the α decay preformation factor Pα 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 α decay half-lives of 64 even-even nuclei with 104 Z 128 whose α decay is energetically allowed or observed but not yet quantified. For comparing, the two famous models i.e. SemFIS proposed by D. Poenaru et al. [Europhys. Lett. 77 (2007) 62001] and UDL proposed by C. 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 α decay energy Qα of Z = 118, 120, 122, 124, 126 and 128 isotopes nuclei with the increasing of neutron number N and that of α decay preformation factor Pα of those isotopes even-even nuclei with the increasing of neutron number N, N = 178 may be a new neutron magic number.

In the present work, we predict the α decay half-lives of unknown even-even nuclei296–308120 within the two-potential approach, whose α decay energy Qα is calculated using WS3+ mass model. To reduce the deviations between the predictions and experimental data due to nuclear shell effect, the analytic formula of α decay hindrance factor is introduced to the two-potential approach, whose parameters had been extracted from even-even nuclei in the region of 82 < Z ≤ 126 and 152 < N ≤ 184 in our previous work [Deng et al., Chin. Phys. C 42 (2018) 044102]. In addition, for comparing, we use a type of α decay general formula Universal Decay Law (UDL) and a semi-empirical formula in the superheavy nucleus (SEMFLS) to calculate the half-lives of even-even nuclei296–308120. The results indicate that our predicted values and the calculated values of the above two empirical formulas are mutually confirmed. Meanwhile, we systematically study α decay chains of296–308120 and predict the decay modes for superheavy nuclei to help to identify new superheavy isotopes.