论文标题
$α+α$系统中的弹性散射，相移和辐射捕获反应截面的R-Matrix分析
R-matrix analysis of elastic scattering, phase shift and radiative capture reaction cross sections in the $α+ α$ system
论文作者
论文摘要
不稳定的核$^8 $ be，其两种$α$ -Cluster配置，是形成更重的$α$ cluster核的门口。最重要的是，它是通过霍伊尔州（Hoyle State）在大型恒星的氦气燃烧阶段中产生$^{12} $ c的先驱。该核表现出通过$α-α$散射实验建立的旋转状态的基态谱带。随后的精度粒子-UMγ$的重合测量值在4 $^+\ rightarrow $ 2 $^+$兴奋状态之间的电磁过渡之间也证实了证据，以证明$^8 $的高度变形哑铃形状结构。已经进行了测量的捕获反应截面的同时现象学R-Matrix分析以及弹性激发函数和相移数据。结果降低的过渡强度为21.96 $ \ pm $ 3.86 $ e^2 fm^4 $与估计的实验值21.0 $ \ pm $ 2.3 E $^2 $ fm $^4 $相比。 B（$ e2 $）值的R-Matrix收益率更接近群集模型的预测，但比{\ it Ab intibil}结果小约19 $ \％$。
The unstable nucleus $^8$Be, with its two $α$-cluster configuration, is the doorway to the formation of heavier $α$-cluster nuclei. Most importantly, its the precursor of the production of $^{12}$C through the Hoyle state, a resonance state of three $α$ clusters, in the helium burning phase of a massive star. The nucleus exhibits a ground state band of rotational states established through $α-α$ scattering experiments. A subsequent precision particle-$γ$ coincidence measurement of the electromagnetic transition between the 4$^+\rightarrow$ 2$^+$ excited states also corroborated the evidence for a highly deformed dumb-bell shaped structure of $^8$Be. A simultaneous phenomenological R-matrix analysis of the measured capture reaction cross sections along with the elastic excitation function and phase shift data has been performed. The resulting reduced transition strength of 21.96$\pm$3.86 $e^2 fm^4$ compares well with the estimated experimental value of 21.0$\pm$2.3 e$^2$ fm$^4$. The R-matrix yield of the B($E2$) value is closer to the prediction of cluster model but about 19$\%$ less than the {\it ab initio} result.
