No chance for synthesis of super-heavy nuclei in fusion of symmetric systems

作者：Cap T; Siwek Wilczynska K; Wilczynski J^*

来源：Physics Letters B, 2014, 736: 478-481.

DOI：10.1016/j.physletb.2014.07.062

• Fusion-by-diffusion model
• Super-heavy nuclei
• Symmetric systems

Predictions of relatively large cross sections (of about 1 picobarn) for synthesis of super heavy nuclei of Z = 122 and Z = 124 in cold fusion (1n) reactions of symmetric Sm-154 + Nd-150 and Sm-154 + Sm-154 systems by R.K. Choudhury and Y.K. Gupta (2014) [1] are examined. The authors state that this result had been obtained by using the fusion-by-diffusion (FBD) model. As predictions of the original FBD model of Swiatecki, Cap, Siwek-Wilczynska and Wilczynski had been definitely pessimistic regarding fusion of more symmetric systems (in comparison with equivalent asymmetric systems), we feel compelled to present excitation functions of the Sm-154(Nd-150, 1n)(303)122 and Sm-154(Sm-154, 1n)(307)124 reactions, calculated within the original fusion-by-diffusion model. In accordance with our earlier predictions of a general trend of fusion hindrance for near-symmetric systems, the cross sections for synthesis of (303)122 and (307)124 nuclides in fusion of these two symmetric systems are found to be extremely small and probably never reachable: about 10(-11) pb and 10(-13) pb, respectively. It is shown that Choudhury and Gupta obtained their results (overestimating the cross sections by 11 and 13 orders of magnitude) as an effect of an arbitrary and physically unjustified interference in the FBD model.

• 出版日期2014-9-7