Shell effects in the symmetric-modal fission of pre-actinide nuclei

• Published in: Nuclear physics. A Vol. 640; no. 3; pp. 375 - 388
• Main Authors: Mulgin, S.I., Schmidt, K.-H., Grewe, A., Zhdanov, S.V.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 21.09.1998
• Subjects: Fission-fragment mass distributions; Nuclear fission; Pre-actinides ( A ≈ 180–220); Semiempirical fission model; Shell effects; Symmetric fission mode; 21.10.Ma; Symmetric fission mode; Shell effects; 27.80.+w; Semiempirical fission model; 24.10.−i; 25.85.Ge; Pre-actinides ( A ≈ 180–220); 24.60.Dr; Fission-fragment mass distributions; 25.85.−w; Nuclear fission; 24.75.+i
• ISSN: 0375-9474
• DOI: 10.1016/S0375-9474(98)00332-7

Mass distributions of fragments in the low-energy fission of nuclei from 187Ir to 213At have been analysed. This analysis has shown that shell effects in symmetric-mode fragment mass yields from the fission of pre-actinide nuclei could be described if one assumes the existence of two strongly deformed neutron shells in the arising fragments with neutron numbers N 1 ≈ 52 and N 2 ≈ 68. A new method has been proposed for quantitatively describing the mass distributions of the symmetric fission mode for pre-actinides with A ≈ 180–220.