Isoscalar giant resonances in the Sn nuclei and implications for the asymmetry term in the nuclear-matter incompressibility
Isoscalar giant resonances in the Sn nuclei and implications for the asymmetry term in the nuclear-matter incompressibility
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DOI：
10.1103/physrevc.81.034309
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发表时间：
2010-02
影响因子：
3.1
通讯作者：
T. Li;U. Garg;E. al.
中科院分区：
文献类型：
--
作者：
T. Li;U. Garg;E. al.
我们已经研究了在锡同位素的isoscillator巨共振使用非弹性散射的386 MeV的α粒子在非常向前的角度，包括0度。我们已经获得了完全“背景自由”的非弹性散射光谱的Sn同位素的角度范围0度-9度和高达31.5 MeV的激发能量。根据各个多极子的预期角分布，通过多极子分解分析提取各种多极子的强度分布。我们发现Sn同位素的等oscillator巨磁共振（ISGMR）的质心能量明显低于理论预测。此外，根据ISGMR结果，得到了核不可压缩性中不对称项的K（tau）= -550 +/-100 MeV。在实验获得的K（无穷大）和K（τ）值的基础上，讨论了核结构计算中所采用的相互作用的约束。
We have investigated the isoscalar giant resonances in the Sn isotopes using inelastic scattering of 386-MeV alpha particles at extremely forward angles, including 0 degrees. We have obtained completely "background-free" inelastic-scattering spectra for the Sn isotopes over the angular range 0 degrees-9 degrees and up to an excitation energy of 31.5 MeV. The strength distributions for various multipoles were extracted by a multipole decomposition analysis based on the expected angular distributions of the respective multipoles. We find that the centroid energies of the isoscalar giant monopole resonance (ISGMR) in the Sn isotopes are significantly lower than the theoretical predictions. In addition, based on the ISGMR results, a value of K(tau) = -550 +/- 100 MeV is obtained for the asymmetry term in the nuclear incompressibility. Constraints on interactions employed in nuclear structure calculations are discussed on the basis of the experimentally obtained values for K(infinity) and K(tau).