用于更好的光学模型的统计工具
Statistical tools for a better optical model
摘要：
背景资料：现代统计工具提供了比较可观测量的信息内容的能力，并提供了一条探索哪些实验对洞察和约束理论模型最有用的路径。目的：在这项工作中，我们研究了三个这样的工具的背景下，核反应的目标是限制的光学势。方法：研究的三种统计工具是：i）主成分分析; ii）基于衍生工具的敏感性分析; iii）贝叶斯证据。我们首先将这些工具应用到一个玩具模型的情况下，比较光学势的虚部的形式。然后，我们考虑两个不同的反应观测，弹性角分布和极化数据的反应48 Ca在两个不同的光束能量。结果如下：对于玩具模型的情况下，我们发现显着的歧视权力的灵敏度和贝叶斯证据，清楚地表明，体积虚项是更有用的描述在更高的能量散射。当比较弹性截面和偏振数据使用现实的光学模型，灵敏度研究表明，这两个可观的是大致同样敏感，但光学模型参数的变化是强烈的角度依赖。贝叶斯证据表明两个观测值之间存在一定的变异性，但贝叶斯因子不足以区分角分布和偏振。结论：从所考虑的情况下，我们得出结论，在一般情况下，弹性散射角分布有类似的影响，在约束的光学势参数相比，偏振数据。最佳实验约束的角度范围可以随着所考虑的可观察性而显著变化。
英文摘要：
Background: Modern statistical tools provide the ability to compare the information content of observables and provide a path to explore which experiments would be most useful to give insight into and constrain theoretical models. Purpose: In this work we study three such tools in the context of nuclear reactions with the goal of constraining the optical potential. Method: The three statistical tools examined are: i) the principal component analysis; ii) the sensitivity analysis based on derivatives; and iii) the Bayesian evidence. We first apply these tools to a toy-model case, comparing the form of the imaginary part of the optical potential. Then we consider two different reaction observables, elastic angular distributions and polarization data for reactions on 48Ca at two different beam energies. Results: For the toy-model case, we find significant discrimination power in the sensitivities and the Bayesian evidence, showing clearly that the volume imaginary term is more useful to describe scattering at higher energies. When comparing between elastic cross sections and polarization data using realistic optical models, sensitivity studies indicate that both observables are roughly equally sensitive but the variability of the optical model parameters is strongly angle dependent. The Bayesian evidence shows some variability between the two observables, but the Bayes factor obtained is not sufficient to discriminate between angular distributions and polarization. Conclusions: From the cases considered, we conclude that in general elastic scattering angular distributions have similar impact in constraining the optical potential parameters compared to the polarization data. The angular ranges for the optimum experimental constraints can vary significantly with the observable considered.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
