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Effects of shell structure in reactions leading to the same compound nucleus or different isotopes

A. K. Nasirov·G. Fazio·G. Giardina·A. Lamberto·R. Ruggeri·A. Taccone·A. I. Muminov·F. Hanappe·R. Palamara·L. Stuttg'e
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Abstract

The role of the entrance channel in fusion-fission reactions was studied by the theoretical analysis of the experimental evaporation residue excitation functions for reactions leading to the same compound nucleus. The evaporation residues cross sections for xn-channels were calculated in the frame of the combined dinuclear system concept and advanced statistical model. The revealed differences between experimental data on the evaporation residues in the ^{40}Ar+^{176}Hf, ^{86}Kr + ^{130}Xe and ^{124}Sn + ^{92}Zr reactions leading to the ^{216}Th^* compound nucleus are explained by the different spin distributions of compound nuclei which are formed. It is shown that the intrinsic fusion barrier B^*_{fus} and size of potential well are different for every entrance channel.

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A. K. Nasirov, G. Fazio, G. Giardina, A. Lamberto, R. Ruggeri, A. Taccone, A. I. Muminov, F. Hanappe, R. Palamara, L. Stuttg'e. 2001-11-13. Effects of shell structure in reactions leading to the same compound nucleus or different isotopes. https://doi.org/10.1142/9789812778321_0038

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