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In this paper, we have made an attempt to analyze the alpha-decay half-lives of in the atomic number range $62\le Z\le 118$ by considering an effective liquid drop model. The role of pre-formation probability by including iso-spin effect is included during an evaluation of half-lives. We have also compared the studied alpha-decay half-lives with that of semi-empirical formulae such as Viola Seaborg semi-empirical formulae (VSS) [J. Inorg. Nucl. Chem. 28 (1966) 741; Nucl. Phys. A 848 (2010) 279], Royer formulae [J. Phys. G: Nucl. Part. Phys. 26 (2000) 1149; Phys. Rev. C 101 (2020) 034307] and also with that of the available experiments. From this comparison, it can be concluded that the effective liquid drop model produces an alpha-decay half-lives close to the experiments.

Recent experiments using actinide + ⁴⁸Ca reactions have led to the discovery of five new elements and more than 50 new isotopes on the “hot fusion” island. These new nuclei, all having a large neutron excess over protons, provide strong evidence for the existence of the proposed island of stability for superheavy nuclei. As atomic number Z increases beyond Z = 115, the reaction cross sections are decreasing, requiring new approaches for continued progress. Ion beams heavier than ⁴⁸Ca will be required to reach elements above Z = 118, and new actinide target technologies and separation capabilities will be needed to accommodate higher beam intensities and optimize the use of heavier ²⁵¹Ca targets in experiments. In this paper, we review the availability of actinide materials, the use of new target/projectile combinations, and related experimental opportunities, including prospects for new element discoveries and for approaching the presumed closed shell at N = 184. Research opportunities include ongoing experiments to produce the heaviest nuclei to date using mixed Cf targets, and measurements of excitation functions for ⁴⁸Ca and ⁵⁰Ti on Pu and Cm targets to estimate cross sections for planned experiments using ⁵⁰Ti beams on ²⁴⁹Bk and ²⁵¹Cf for synthesis of elements 119 and 120. New developments for the production of ²⁴⁹Bk and for increasing the availability of ²⁵¹Cf and possibly ²⁵⁴Es are described.

The Heavy Shell Model (HSM) is introduced as an extended Projected Shell Model (PSM), which combines the advantages of two existing models, the PSM and the Fermion Dynamical Symmetry Model (FDSM). As a First numerical realization of the HSM, the energy scheme and B(E2) values of ²³⁴U are reproduced and agree with observed experimental data quite well. Some predicted low-lying bands have not yet been measured, remaining to be tested experimentally.

Development of gamma-ray beam interrogation technologies for remote detection of special nuclear materials and isotope analysis requires comprehensive databases of nuclear structure information and gamma-ray induced nuclear reaction observables. Relevant nuclear structure details include the energy, spin and parity of excited states that have significant probability for electromagnetic transition from the ground state, i.e, the angular momentum transferred in the reaction is Δl ≤ 2. This talk will report recent Nuclear Resonance Fluorescence (NRF) measurements to identify and characterize new low-spin states in actinide nuclei at energies from 1 to 4 MeV, which is the energy range most important for remote analysis methods. These measurements are carried out using the nearly mono-energetic linearly polarized gamma-ray beam at the High Intensity Gamma-ray Source (HIγS) at the Triangle Universities Nuclear Laboratory. Also, studies of the (γ, n) reaction on a variety of nuclei with linearly polarized beams at HIγS indicate that this reaction might be used to discern between fissile and non-fissile materials. This work will be described. In addition, an overview will be given of a concept for a next generation laser Compton-backing scattering gamma-ray source to be implemented as an upgrade to increase the beam intensity at HIγS by more than an order of magnitude.