摘要
Within the framework of the dinuclear system model, the capture of two colliding nuclei, and the formation and de-excitation process of a compound nucleus are described by using an empirical coupled channel model, solving the master equation numerically and the statistical evaporation model, respectively. In the process of heavy-ion capture and fusion to synthesize superheavy nuclei, the barrier distribution function is introduced and averaging collision orientations are considered. Based on this model, the production cross sections of the cold fusion system ^76-82Se+^209Bi and the hot fusion systems ^55Mn+^238U, ^51V+^244pu, ^59Co+^232Th, ^48Ca+^247-249Bk and ^45Sc+^246-248Cm are calculated. The isotopic dependence of the largest production cross sections is analyzed briefly, and the optimal projectile-target combination and excitation energy of the 1n-4n evaporation channels are proposed. It is shown that the hot fusion systems ^48Ca+^247-249Bk in the 3n evaporation channels and ^45Sc+248Cm in the 2n-4n channels are optimal for synthesizing the superheavy element 117.
Within the framework of the dinuclear system model, the capture of two colliding nuclei, and the formation and de-excitation process of a compound nucleus are described by using an empirical coupled channel model, solving the master equation numerically and the statistical evaporation model, respectively. In the process of heavy-ion capture and fusion to synthesize superheavy nuclei, the barrier distribution function is introduced and averaging collision orientations are considered. Based on this model, the production cross sections of the cold fusion system ^76-82Se+^209Bi and the hot fusion systems ^55Mn+^238U, ^51V+^244pu, ^59Co+^232Th, ^48Ca+^247-249Bk and ^45Sc+^246-248Cm are calculated. The isotopic dependence of the largest production cross sections is analyzed briefly, and the optimal projectile-target combination and excitation energy of the 1n-4n evaporation channels are proposed. It is shown that the hot fusion systems ^48Ca+^247-249Bk in the 3n evaporation channels and ^45Sc+248Cm in the 2n-4n channels are optimal for synthesizing the superheavy element 117.
基金
Supported by Major State Basic Research Development Program of China (2007CB815001)
National Natural Science Foundation of China (10975119,10979066)
Knowledge Innovation Project of Chinese Academy of Sciences (KJCX3-SYW-N02,KJCX2-YW-N32)