分类: 物理学 >> 核物理学 提交时间: 2024-04-18
摘要: Based on the dinuclear system model, the calculated evaporation residue cross sections matched well with the current experimental results. The synthesis of superheavy elements Z = 121 was systematically studied through combinations of stable projectiles with Z = 21–30 and targets with half-lives exceeding 50 d. The influence of mass asymmetry and isotopic dependence on the projectile and target nuclei was investigated in detail. The reactions 254Es (46Ti, 3n) 297121 and 252Es (46Ti, 3n) 295121 were found to be experimentally feasible for synthesizing superheavy element Z = 121, with maximal evaporation residue cross sections of 6.619 and 4.123 fb at 219.9 and 223.9 MeV, respectively.
分类: 物理学 >> 核物理学 提交时间: 2024-02-05
摘要: The feasibility of producing superheavy nuclei in proton evaporation channels was systematically studied within the dinuclear system (DNS) model. Due to the Z=114 proton-shell, one can synthesize Fl isotopes in proton evaporation channels. We only considered the case of evaporating one proton first and then n neutrons in this work, other cases were ignored due to the small cross-section. The production cross sections of unknown isotopes 290,291Fl in 38S+255Es reaction are the highest compared with 50Ti+243Np and 54Cr+239Pa reactions, and the maximum cross sections are 1.1 and 15.1 pb, respectively. 42S+254Es is a promising candidate to approach the island of stability as the radioactive beam facilities are upgraded in the future, and the production cross sections of 291294Fl in that reaction are estimated to be 3.2, 6.0, 4.0, and 0.1 pb, respectively.