Fragment spin as a function of the mass asymmetry in heavy ion induced fission reactions

被引：28

作者：

Choudhury, RK ^{[1
]}

Saxena, A

Chatterjee, A

Shetty, DV

Kapoor, SS

Cinausero, M

Corradi, L

Farnea, E

Fioretto, E

Gadea, A

Napoli, D

Prete, G

Stefanini, AM

Bazzaco, D

Beghini, S

Fabris, D

Montagnoli, G

Nebbia, G

Rossi-Alvarez, C

Scarlassara, F

Ur, C

Viesti, G

机构：

[1] Bhabha Atom Res Ctr, Div Nucl Phys, Mumbai 400085, India

[2] Lab Nazl Legnaro, I-35020 Legnaro, Italy

[3] Univ Padua, Dipartimento Fis, Padua, Italy

[4] Ist Nazl Fis Nucl, Sez Padova, Padua, Italy

来源：

PHYSICAL REVIEW C | 1999年 / 60卷 / 05期

关键词：

D O I：

10.1103/PhysRevC.60.054609

中图分类号：

O57 [原子核物理学、高能物理学];

学科分类号：

070202 ;

摘要：

The total average spins of fission fragments were measured as a function of fragment mass in C-12, O-16 + Bi-209 and C-12, O-16+ Th-232 reactions at bombarding energies near and above the Coulomb barrier. The mass dependence of the fragment spin for the C-12, O-16+ Th-232 reactions is observed to be in marked contrast to that for the C-12, O-16+ Bi-209 reactions. The present results have been analyzed within the framework of the statistical model taking into account the finite relaxation times for the equilibration of the collective-spin modes. The observed features in C-12, O-16+ Th-232 reactions can be ascribed to incomplete equilibration of the collective-spin modes where the mass relaxation at extreme mass asymmetries terminates before full statistical equilibration of the collective-spin modes is reached. [S0556-2813(99)04110-2].

引用

页数：8

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