Theoretical Study of Structure and Synthesis Mechanism of Superheavy Nuclei

Key words: 
• superheavy nuclei /
• particle number conserving method /
• cranked shell model /
• covariant density functional theory /
• heavy-ion fusion reaction /
• di-nuclear system model

Abstract: The exploration of charge and mass limits of atomic nuclei and the synthesis of long-lived or stable superheavy nuclei (SHN) are on the frontier of modern nuclear physics. Recent theoretical progresses made by us on the study of structure and synthesis mechanism of SHN are reviewed. The study of structure properties includes a systematic study of low-lying spectra of actinide and transfermium nuclei by using a cranked shell model with the pairing treated by a particle number conserving method (PNC-CSM), the study of potential energy surfaces and fission barriers of actinide nuclei and non-axial octupole correlations in N = 150 isotones by using newly-developed multi-dimensional constraint covariant density functional theories (MDCCDFT).The study of the synthesis mechanism of SHN is carried out by examining in details of the three steps in producing SHN via heavy-ion fusion reactions: i) For the capture process, a new barrier penetration formula is proposed for potential barriers containing a long-range Coulomb interaction; ii) For the fusion process, a dinuclear system model with a dynamical potential energy surface (the DNS-DynPES model) is developed; and iii) For the survival process, a systematic study of the survival probability against fission in the 1n-channel of SHN with 100 6 Z 6 134 is made and it is found that the survival probability in the 1n-channel is mainly determined by the nuclear shell effects. By using the DNS-DynPES model, hot fusion reactions for synthesizing SHN with charge numbers Z =112s120 are studied. The calculated evaporation residue cross sections are in good agreement with available data and predictions are made for synthesizing SHN with Z=119 and 120.