标题： 反应中$^{10}$He 态的异常种群与$^{11}$Li 显示英文标题

标题： Anomalous population of $^{10}$He states in reactions with $^{11}$Li

摘要： 在用$^{11}$Li 束流进行质子剥离反应中观察到的$^{10}$He 谱中能量最低的结构在$1.2-1.5$MeV 处有一个峰。 该峰通常被解释为共振的$0^+$基态的$^{10}$He。 我们的理论计算表明，这个峰可能是$1^-$、$0^+$和$2^+$激发态的叠加，它们具有非常相似的形状。 %我们预测了$1^-$激发态在$^{10}$He 中的非常具体的性质。 此外，“软”$1^-$激发态似乎能量最低。 这种异常的连续谱响应归因于$^{11}$Li 的晕结构，它为所有预期的连续谱激发态提供了极端低能位移。 初始状态结构（ISS）和最终状态相互作用（FSI）效应对$^{10}$He 谱和三体关联的影响进行了讨论。 在其他由晕核反应产生的$2n$放射性核素情况下，也可以预期类似的极端低能位移效应。 给出了$^{10}$He 在$\alpha$从$^{14}$Be 中剥离的谱的简化示例。 我们还讨论了从观测到的$^{10}$He 谱中得出的$^{9}$He 特性的限制。 显示英文摘要

摘要： Structure with the lowest energy observed in the $^{10}$He spectrum populated in the proton knockout reaction with $^{11}$Li beam has a peak at $1.2-1.5$ MeV. This peak is usually interpreted as a resonant $0^+$ ground state of $^{10}$He. Our theoretical calculations indicate that this peak is likely to be a pileup of $1^-$, $0^+$, and $2^+$ excitations with very similar shapes. %We predict a very specific nature of the $1^-$ excitation in $^{10}$He. Moreover, the ``soft'' $1^-$ excitation appears to be the lowest one in energy. Such an anomalous continuum response is traced to the halo structure of $^{11}$Li providing extreme low energy shift to all the expected continuum excitations. Competitions of the initial state structure (ISS) and the final state interaction (FSI) effects on the spectrum and three-body correlations in $^{10}$He are discussed. Analogous effect of the extreme low-energy shift could also be expected in other cases of $2n$ emitters populated in reactions with halo nuclei. Simplified example of the $^{10}$He spectrum in $\alpha$ knockout from $^{14}$Be, is given. We also discuss limits on the properties of $^{9}$He stemming from the observed $^{10}$He spectrum.