摘要
<Abstract>The influence of isospin on the excess of evaporation residue cross section over its standard statistical-model value for nuclei ^(194)Pb,^(200)Pb,and ^(206)pb is studied via a Langevin equation coupled with a statistical decay model.The magnitude of this excess for a low-isospin fissioning nucleus is shown to be larger and its dependence on the nuclear viscosity coefficient to be stronger than those of a high-isospin fissioning nucleus.These results suggest that to obtain a more accurate information of viscosity coefficient inside the saddle point by measuring evaporation residue cross sections, we had better choose those compound systems with small isospin.
The influence of isospin on the excess of evaporation residue cross section over its standard statistical-model value for nuclei ^194pb, ^200Pb, and ^206pb is studied via a Langevin equation coupled with a statistical decay model. The magnitude of this excess for a low-isospin fissioning nucleus is shown to be larger and its dependence on the nuclear viscosity coefficient to be stronger than those of a high-isospin fissioning nucleus. These results suggest that to obtain a more accurate information of viscosity coefficient inside the saddle point by measuring evaporation residue cross sections, we had better choose those compound systems with small isospin.
基金
supported by National Natural Science Foundation of China under Grant No.10405007
关键词
核物理
同位旋
蒸发残渣
原子核
evaporation residue cross section, isospin effect, nuclear dissipation, Langevin equation