论文标题
$ e1 $ $^11 $ li的最终国家互动和旋转结构在Halo eft中
Final-state interactions and spin structure in $E1$ breakup of $^11$Li in Halo EFT
论文作者
论文摘要
我们计算出$ 2N $ halo nucleus $^{11} $ li的$ e1 $分解。在Halo eft中，$^{11} $ li被视为$^{9} $ li core和两个中子的三体系统。我们介绍了对中子中子$（NN）$和中子核$（NC）$ channels中最终国家互动（FSI）的详细调查。我们采用moller运算符来制定满足非能量加权群集总和规则的扩展方案，并在FSI的多片段序列中连续包含高阶术语。在此方案中，计算$ E1 $强度最高三阶，我们观察到与实验明显的收敛和良好的一致性。中子中子中子FSI是迄今为止最重要的贡献，并在很大程度上决定了$ e1 $分布的最大值。但是，包含$ NC $ FSI的确会将峰位置转移到略低的能量。此外，我们研究了$ e1 $响应中子的旋转结构的灵敏度 - $ {}^9 $ li相互作用。我们将在Spin-1和Spin-2通道中相同的相互作用与仅在SPIN-2通道中起作用的相互作用相同的相互作用进行对比，并且发现仅当两个自旋通道中存在相互作用时才能获得与实验数据的良好一致性。后一种情况被证明等同于忽略$^9 $ li的旋转的计算。
We calculate the $E1$ breakup of the $2n$ halo nucleus $^{11}$Li in Halo Effective Field Theory (Halo EFT) at leading order. In Halo EFT, $^{11}$Li is treated as a three-body system of a $^{9}$Li core and two neutrons. We present a detailed investigation of final-state interactions (FSI) in the neutron-neutron $(nn)$ and neutron-core $(nc)$ channels. We employ Moller operators to formulate an expansion scheme that satisfies the non-energy-weighted cluster sum rule and successively includes higher-order terms in the multiple-scattering series for the FSI. Computing the $E1$ strength up to third order in this scheme, we observe apparent convergence and good agreement with experiment. The neutron-neutron FSI is by far the most important contribution and largely determines the maximum value of the $E1$ distribution. However, inclusion of $nc$ FSI does shift the peak position to slightly lower energies. Moreover, we investigate the sensitivity of the $E1$ response to the spin structure of the neutron-${}^9$Li interaction. We contrast results for an interaction that is the same in the spin-1 and spin-2 channels with one that is only operative in the spin-2 channel, and find that good agreement with experimental data is only obtained if the interaction is present in both spin channels. The latter case is shown to be equivalent to a calculation in which the spin of $^9$Li is neglected.
