7 Be(n,a) and 7 Be(n,p) cross-section measurement for the cosmological lithium problem at the n_TOF facility at CERN
7 Be(n,a) and 7 Be(n,p) cross-section measurement for the cosmological lithium problem at the n_TOF facility at CERN
复制标题
CERN n_TOF 设施中宇宙学锂问题的 7 Be(n,a) 和 7 Be(n,p) 横截面测量
DOI：
10.1051/epjconf/201714601012
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发表时间：
2017
影响因子：
--
通讯作者：
Barbagallo M
中科院分区：
文献类型：
--
作者：
Barbagallo M
宇宙锂问题是指大爆炸核合成标准理论预测的原始锂丰度与晕星中所谓的“Spite坪”之间的巨大差异。对于这个在核天体物理学中长期存在的谜团，一个可能的解释是与对7Be的破坏率的错误估计有关，7Be负责产生95%的原始锂。虽然带电粒子引发的反应大部分已经被排除，但7Be（n，α）和7Be（n，p）反应的数据很少或完全缺失，因此很大的不确定性仍然影响着大爆炸核合成标准理论预测的7Li丰度。这两种反应都在欧洲核子研究中心的n_TOF设施上进行了测量，首次提供了宽中子能量范围内的数据。
The Cosmological Lithium Problem refers to the large discrepancy between the abundance of primordial7Li predicted by the standard theory of Big Bang Nucleosynthesis and the value inferred from the so-called “Spite plateau” in halo stars. A possible explanation for this longstanding puzzle in Nuclear Astrophysics is related to the incorrect estimation of the destruction rate of7Be, which is responsible for the production of 95% of primordial Lithium. While charged-particle induced reactions have mostly been ruled out, data on the7Be(n,α) and7Be(n,p) reactions are scarce or completely missing, so that a large uncertainty still affects the abundance of7Li predicted by the standard theory of Big Bang Nucleosynthesis. Both reactions have been measured at the n_TOF facility at CERN, providing for the first time data in a wide neutron energy range.