Production cross sections of superheavy elements: insights from the dinuclear system model with high-quality microscopic nuclear masses

摘要: To accurately predict the synthesis cross sections of unknown superheavy elements, identify the optimal projectile-target combinations and the evaporation channels at specific bombarding energies, we incorporate high-quality microscopic nuclear masses (HQMNM) into the dinuclear system (DNS) model to perform calculations; these masses are obtained from a Skyrme energy-density-functional fit to measured $\alpha$-decay energies [Phys. Lett. B 851 (2024) 138578]. Because the DNS model is highly sensitive to Q-values, binding energy, shell correction energy, pairing energy, and separation energy, adopting precise nuclear masses is essential. Calculations for hot-fusion reactions reproduce existing experimental data and surpass the accuracy achieved with the finite-range droplet model (FRDM12). A benchmark calculation for the hot-fusion reaction $^{48}$Ca + $^{243}${\rm Am} $\rightarrow$ $^{291}$Mc$^*$ was performed to quantify the influence of the HQMNM on capture, fusion, and evaporation probabilities. Based on this reference, systematic calculations within the DNS model incorporating the HQMNM are extended to other hot-fusion systems and compared with available experimental excitation functions, demonstrating the model’s superior predictive power. We further systematically evaluate all viable projectile–target combinations for synthesizing elements 119 and 120. Predicted evaporation residue cross sections, optimal excitation energies, and favored decay channels are presented, including \(^{50}\text{Ti}(^{249}\text{Bk},3n)^{296}119\) with \(\sigma_{\text{ER}} = 5.16\ \text{fb}\) at \(E^{*}_{\text{CN}} = 36\ \text{MeV}\), and \(^{50}\text{Ti}(^{249}\text{Cf},3n)^{296}120\) with \(\sigma_{\text{ER}} = 4.35\ \text{fb}\) at \(E^{*}_{\text{CN}} = 34\ \text{MeV}\). These results offer quantitative guidance for future experiments.