arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 2609.25320astro-ph.CO

两点相关函数的基函数展开与宇宙学距离尺度的重建

Basis function expansions of the two-point correlation function and reconstruction of the cosmological distance scale

Fatima Abd Alrahman, Farnik Nikakhtar, Marcello Musso, Aseem Paranjape, Ravi K. Sheth

首次发表
浏览论文内容

中文总结 AI 辅助

本文提出利用多项式与半整数广义拉盖尔函数作为基函数,将星系对计数投影到正交基上,从而在不分箱的单一步骤中测量两点相关函数并重建宇宙学距离尺度,同时考虑了散粒噪声与宇宙方差的影响。

中文摘要 AI 辅助

星系对相关函数的形状可用作宇宙学距离指示器。大多数对该形状的估计方法要求对星系对计数进行分箱,并且需要花费大量精力来寻找最优的箱尺寸。随后,通过拟合分箱后的星系对计数,在单独的步骤中推导出宇宙学约束。通过将星系对计数投影到合适的基函数集上,可以在不分箱的情况下估计星系对相关函数。近期研究表明,在从星系成团数据估计宇宙学距离尺度的背景下,多项式与半整数广义拉盖尔函数是特别有用的基函数。我们展示了如何利用这些基函数在单一步骤中测量相关函数并估计重建的距离尺度。我们的分析包含了散粒噪声和宇宙方差的影响,并强调了将星系对计数投影到正交基函数上的优势。

英文摘要

The shape of the correlation function of galaxy pairs can be used as a cosmological distance indicator. Most estimators of this shape require that one bin the pair counts, and considerable effort is expended in finding the optimal bin size. Cosmological constraints are then derived, in a separate step, by fitting to the binned pair counts. By projecting the pair counts on a suitable basis set, it is possible to estimate the pair correlation function without binning. Recent work suggests that, in the context of estimating the cosmological distance scale from galaxy clustering data, polynomials and half-integer generalized Laguerre functions are particularly useful bases. We show how to use these bases to measure the correlation function and estimate the reconstructed distance scale in a single step. Our analysis includes the effects of shot-noise and cosmic variance, and highlights the benefits of projecting pair counts onto orthogonal basis functions.

发表机构

  • ICTP East Africa Institute for Fundamental Research, University of Rwanda(东非基础研究所,卢旺达大学)
  • Department of Physics, University of Houston(休斯顿大学物理系)
  • Department of Physics, University of Khartoum(喀土穆大学物理系)
  • Department of Physics, Yale University(耶鲁大学物理系)
  • Departamento de Física Fundamental & IUFFyM, Universidad de Salamanca(萨拉曼卡大学基础物理系及IUFFyM)
  • Inter-University Centre for Astronomy & Astrophysics(大学间天文学与天体物理学中心)
  • Center for Particle Cosmology, University of Pennsylvania(宾夕法尼亚大学粒子宇宙学中心)

机构由 AI 辅助整理,请以论文原文为准。

补充信息

↑