论文标题
在Lyman-$α$ Forest中安装BARYON声学振荡的贝叶斯方法
Bayesian methods for fitting Baryon Acoustic Oscillations in the Lyman-$α$ forest
论文作者
论文摘要
我们研究和比较lyman-$α$（ly $α$）森林3D相关函数的拟合方法。我们使用嵌套的采样器Polychord和社区代码PICCA进行贝叶斯分析，我们将其与以前的频繁分析进行了比较。通过研究合成相关函数，我们发现频繁的曲线可能性与完整的贝叶斯分析产生了良好的一致性。另一方面，对于当前数据集，不确定性的高斯近似值的最大似然估计不足。我们首次计算通过扩展的Baryon振荡光谱调查（EBOSS）测量的LY $α$森林相关功能的全部后验分布。我们通过扩展基线分析来更好地了解阻尼$α$ Systems（DLAS）的污染，从而强调了对完整后验分布的好处。作为PICCA软件包的一部分，我们将改进和结果公开提供。
We study and compare fitting methods for the Lyman-$α$ (Ly$α$) forest 3D correlation function. We use the nested sampler PolyChord and the community code picca to perform a Bayesian analysis which we compare with previous frequentist analyses. By studying synthetic correlation functions, we find that the frequentist profile likelihood produces results in good agreement with a full Bayesian analysis. On the other hand, Maximum Likelihood Estimation with the Gaussian approximation for the uncertainties is inadequate for current data sets. We compute for the first time the full posterior distribution from the Ly$α$ forest correlation functions measured by the extended Baryon Oscillation Spectroscopic Survey (eBOSS). We highlight the benefits of sampling the full posterior distribution by expanding the baseline analysis to better understand the contamination by Damped Ly$α$ systems (DLAs). We make our improvements and results publicly available as part of the picca package.
