Giant resonances in excited Sn isotopes.
Giant resonances in excited Sn isotopes.
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激发态锡同位素中的巨大共振。
DOI：
10.1103/physrevc.36.1886
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发表时间：
1987
期刊：
影响因子：
--
通讯作者：
Gaardhoje
中科院分区：
文献类型：
--
作者：
Chakrabarty;Sen;Thoennessen;Alamanos;Paul;Schicker;Stachel;Gaardhoje
在激发态上建立的巨偶极子共振在/sup 11、112/Sn核中，激发能分别为62、80、110和130 MeV。重离子聚变反应后的射线/sup 16/O+ /sup 94/Mo和/sup 19/F+ /sup 93/Nb。偶极子共振的能量为14.8 +- 0.4 MeV，与激发能无关。这个值大约比外推的基态值低1兆电子伏。宽度从62 MeV时的6.7 MeV增加到130 MeV时的10.8 MeV。这与理论预测一致，即这些原子核宽度的增加主要是由于在高自旋和高温度下引起的各种扁圆形状上的强度函数的平均。发现即使在最高激励能量下，对等矢量四极振动的灵敏度也很小。没有令人信服的结论表明它存在于这些Sn核中。
The giant dipole resonance built on excited states was studied in /sup 110,112/Sn nuclei at excitation energies of 62, 80, 110, and 130 MeV, by measuring ..gamma.. rays following heavy ion fusion reactions /sup 16/O+ /sup 94/Mo and /sup 19/F+ /sup 93/Nb. The energy of the dipole resonance was found to be 14.8 +- 0.4 MeV independent of excitation energy. This value is approximately 1 MeV below the extrapolated ground state value. The width increases almost quadratically from 6.7 MeV at 62 MeV to 10.8 MeV at 130 MeV. This agrees qualitatively with a theoretical prediction that the increase in width for these nuclei is mainly due to an averaging of strength functions over various oblate shapes induced at high spin and temperature. The sensitivity to the isovector quadrupole vibration was found to be small even at the highest excitation energy. No convincing conclusion could be made for its existence in these Sn nuclei.