发表机构
Institute of Radiation Technology, Beijing Academy of Science and Technology; Department of Nuclear Physics, China Institute of Atomic Energy; School of Physics and Materials Science, Anhui University（北京辐射技术研究所，北京 Akademija 科学技术研究院; 原子能科学研究院核物理系; 安徽大学物理与材料科学学院）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究利用 Trojan horse 方法，通过 16O 准自由破裂间接测量了天体物理能量下 12C(12C,α)20Ne 反应的 S*(E) 因子，证实了 Gamow 窗口内 1.5 MeV 附近的共振，并排除了阻碍效应。
AI 中文摘要
天体物理能量下的 12C(12C,α)20Ne 反应对于理解大质量恒星中的碳燃烧过程以及诸如 Ia 型超新星和 X 射线暴等爆炸性天体物理场景至关重要。然而，由于库仑抑制和 Gamow 窗口（1.5±0.3 MeV）附近可能存在的复杂共振结构，直接测量或简单外推其 S*(E) 因子极为困难。THM 方法能够绕过库仑势垒，提供 Gamow 窗口内的数据而无需外推。此前 Tumino 等人利用 THM 方法（以 14N 为 (12C+d) 结构）报道了 1.5 MeV 附近的强共振，这一结果引发了广泛的兴趣和争论，凸显了进一步实验验证的必要性。在本工作中，我们选择 16O（即 (12C+α) 结构）作为 Trojan-horse 核，因为其较低的结合能有利于准自由反应。我们在中国原子能科学研究院（CIAE）的 HI-13 串列加速器上对 12C(16O,αα)20Ne 反应进行了间接测量。通过使用铜束阻止箔，我们在 0 度附近的小角度范围内测量了旁观者 α 粒子，准自由机制预测该区域旁观者 α 粒子浓度最高。基于扭曲波玻恩近似（DWBA）的 THM 方法，我们从测量的三体反应中提取了天体物理能区 12C(12C,α)20Ne 反应的 S*(E) 因子。我们的结果证实了在 α0 和 α1 两个道中，Gamow 窗口内 1.5 MeV 附近存在共振。在不考虑共振结构细节的情况下，我们结果的总体趋势与 THM-Tumino2018 和 TTIK2025 的数据定性上合理一致，但与 Modified-THM-Muk2019 数据的趋势存在显著差异。在我们的结果中未观察到阻碍效应的证据。
英文摘要
The 12C(12C,a)20Ne reaction at astrophysical energies is crucial for understanding the carbon burning process in massive star and explosive astrophysical scenarios like Type Ia supernovae and X-ray bursts. However, directly measuring or simply extrapolating its S*(E) factor is extremely challenging due to Coulomb suppression and potential complex resonance structures near the Gamow window (1.5+-0.3 MeV). The THM can circumvent the Coulomb barrier, providing data within the Gamow window without extrapolation. Strong resonances near 1.5 MeV were previously reported by Tumino et al. using THM with 14N=(12C+d), a result that generated significant interest and debate, underscoring the need for further experimental verification. In this work, we selected 16O=(12C+a) as the Trojan-horse nucleus due to its lower binding energy, which favors quasi-free reactions. We performed an indirect measurement of 12C(16O,aa)20Ne at the HI-13 Tandem Accelerator at CIAE. Employing a copper beam-stopper foil, we measured the spectator a-particle within a small angular range around 0, where the quasi-free mechanism predicts its highest concentration. The S*(E) factor of 12C(12C,a)20Ne in the astrophysical energy region was extracted from the measured three-body reaction using THM based on DWBA. Our results confirm the existence of resonances within the Gamow window around 1.5 MeV in both the a0 and a1 channels. Without considering the details of the resonance structures, the overall trend of our results is qualitatively in reasonable agreement with the THM-Tumino2018 and TTIK2025 data, but differs significantly from the trend of the Modified-THM-Muk2019 data. We observe no evidence for hindrance effect in our results.
Journal refPhys. Lett. B 879 (2026) 140675
DOI：10.1016/j.physletb.2026.140675
