Influence of entrance-channel magicity and isospin on quasi-fission

被引：112

作者：

Simenel, C. ^{[1
,2
]}

Hinde, D. J. ^{[2
]}

du Rietz, R. ^{[2
]}

Dasgupta, M. ^{[2
]}

Evers, M. ^{[2
]}

Lin, C. J. ^{[2
]}

Luong, D. H. ^{[2
]}

Wakhle, A. ^{[2
]}

机构：

[1] CEA, Ctr Saclay, IRFU Serv Phys Nucl, F-91191 Gif Sur Yvette, France

[2] Australian Natl Univ, Dept Nucl Phys, Res Sch Phys & Engn, Canberra, ACT 0200, Australia

来源：

PHYSICS LETTERS B | 2012年 / 710卷 / 4-5期

关键词：

Nuclear fusion; Quasi-fission; Heavy-element formation; Time-dependent Hartree-Fock theory; FUSION-FISSION; HEAVY; CA-48+PB-208; ELEMENTS;

D O I：

10.1016/j.physletb.2012.03.063

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

The role of spherical quantum shells in the competition between fusion and quasi-fission is studied for reactions forming heavy elements. Measurements of fission fragment mass distributions for different reactions leading to similar compound nuclei have been made near the fusion barrier. In general, more quasi-fission is observed for reactions with non-magic nuclei. However, the Ca-40 + Pb-208 reaction is an exception, showing strong evidence for quasi-fission, though both nuclei are doubly magic. Time-dependent Hartree-Fock calculations predict fast equilibration of N/Z in the two fragments early in the collision. This transfer of nucleons breaks the shell effect, causing this reaction to behave more like a non-magic one in the competition between fusion and quasi-fission. Future measurements of fission in reactions with exotic beams should be able to test this idea with larger N/Z asymmetries. (C) 2012 Elsevier B.V. All rights reserved.

引用

页码：607 / 611

页数：5

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