论文标题
$^{16} $ o(p,$γ$)$^{17} $ f的贝叶斯估算$ s $ ky&k $ kult
Bayesian Estimation of the $S$ Factor and Thermonuclear Reaction Rate for $^{16}$O(p,$γ$)$^{17}$F
论文作者
论文摘要
$^{16} $ O(p,$γ$)$^{17} $ f反应是CNO质量区域中最慢的氢燃烧过程。它的热核速率敏感地影响了包括AGB恒星在内的许多天体物理部位中氧同位素比的预测。使用多种技术在低轰炸能量下测量了几次反应。最新评估的实验率报告的不确定性约为7.5%,低于$ 1 $ 〜GK。但是,先前的速率估计仅代表最佳猜测,并且不是基于严格的统计方法。我们应用贝叶斯模型来适合所有可靠的$^{16} $ O(p,$γ$)$^{17} $ f横截面数据,并考虑到统计和系统不确定性的独立贡献。所采用的核反应模型是涉及产生径向结合状态波函数的木材撒克逊电位的单粒子电位模型。该模型具有三个物理参数:木材 - 撒克逊电位的半径和扩散性,以及最终结合状态的渐近归一化系数(ANC),$^{17} $ f。我们发现,使用ANC作为缩放参数执行贝叶斯$ s $ s $ fixtion拟合比采用光谱因素具有明显的优势。基于这些结果,我们介绍了实验$^{16} $ O(p,$γ$)$^{17} $ f反应速率的第一个统计严格估计,其中不确定性($ \ pm 4.2 $ \%)是先前报道的值的一半。
The $^{16}$O(p,$γ$)$^{17}$F reaction is the slowest hydrogen-burning process in the CNO mass region. Its thermonuclear rate sensitively impacts predictions of oxygen isotopic ratios in a number of astrophysical sites, including AGB stars. The reaction has been measured several times at low bombarding energies using a variety of techniques. The most recent evaluated experimental rates have a reported uncertainty of about 7.5\% below $1$~GK. However, the previous rate estimate represents a best guess only and was not based on rigorous statistical methods. We apply a Bayesian model to fit all reliable $^{16}$O(p,$γ$)$^{17}$F cross section data, and take into account independent contributions of statistical and systematic uncertainties. The nuclear reaction model employed is a single-particle potential model involving a Woods-Saxon potential for generating the radial bound state wave function. The model has three physical parameters, the radius and diffuseness of the Woods-Saxon potential, and the asymptotic normalization coefficients (ANCs) of the final bound state in $^{17}$F. We find that performing the Bayesian $S$ factor fit using ANCs as scaling parameters has a distinct advantage over adopting spectroscopic factors instead. Based on these results, we present the first statistically rigorous estimation of experimental $^{16}$O(p,$γ$)$^{17}$F reaction rates, with uncertainties ($\pm 4.2$\%) of about half the previously reported values.