利用角聚类的重子声学振荡：理论系统误差的优化与缓解
宇宙学与河外天体物理
2018-08-21 v2
摘要
我们研究了利用层析红移区间中的角相关函数测量重子声学振荡(BAO)的方法学及潜在理论系统误差。我们使用1800个模拟样本为暗能量巡天第一年数据集校准并优化管线。我们比较了三种估计量得到的BAO拟合结果：最大似然估计量(MLE)、剖面似然和马尔可夫链蒙特卡洛。去除未探测到BAO信号的极端模拟后，MLE的拟合结果偏差最小，其导出的1-误差棒最接近高斯分布值。我们表明，构建模板时的不正确假设，例如与模拟宇宙学或底层测光红移(photo-)误差的不匹配，可导致BAO角偏移。我们发现MLE是最好追踪此系统偏差的方法，可恢复真实的角距离值。在实际巡天分析中，最终数据样本性质可能略异于模拟星表。我们表明，样本差异对模拟协方差的影响可借助高斯协方差矩阵修正，或更有效地使用模拟协方差的本征模展开来修正。在本征模展开中，本征模由某代理协方差矩阵给出。由于自由参数数量大幅减少，本征模展开相对于协方差矩阵的直接测量显著更不易受统计涨落影响。
引用
@article{arxiv.1801.04390,
title = {BAO from angular clustering: optimization and mitigation of theoretical systematics},
author = {K. C. Chan and M. Crocce and A. J. Ross and S. Avila and J. Elvin-Poole and M. Manera and W. J. Percival and R. Rosenfeld and T. M. C. Abbott and F. B. Abdalla and S. Allam and E. Bertin and D. Brooks and D. L. Burke and A. Carnero Rosell and M. Carrasco Kind and J. Carretero and F. J. Castander and C. E. Cunha and C. B. D'Andrea and L. N. da Costa and C. Davis and J. De Vicente and T. F. Eifler and J. Estrada and B. Flaugher and P. Fosalba and J. Frieman and J. García-Bellido and E. Gaztanaga and D. W. Gerdes and D. Gruen and R. A. Gruendl and J. Gschwend and G. Gutierrez and W. G. Hartley and K. Honscheid and B. Hoyle and D. J. James and E. Krause and K. Kuehn and O. Lahav and M. Lima and M. March and F. Menanteau and C. J. Miller and R. Miquel and A. A. Plazas and K. Reil and A. Roodman and E. Sanchez and V. Scarpine and I. Sevilla-Noarbe and M. Smith and M. Soares-Santos and F. Sobreira and E. Suchyta and M. E. C. Swanson and G. Tarle and D. Thomas and A. R. Walker},
journal= {arXiv preprint arXiv:1801.04390},
year = {2018}
}
备注
23 pages, 23 figs, match to the published version