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Precision cosmology from large-scale galaxy clustering with the Sloan Digital Sky Survey.

机译:斯隆数字天空测量通过大规模星系群集进行的精密宇宙学。

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摘要

We present estimates of cosmological parameters from the application of the linear Karhunen-Loeve (KL) transform technique to the analysis of the three-dimensional power spectrum of density fluctuations using Sloan Digital Sky Survey (SDSS) galaxy redshifts. We use O mh and fb = O b/Om to describe the shape of the power spectrum, sL8g for the (linearly extrapolated) normalization, and beta to parametrize linear theory redshift-space distortions. On scales k ≤ 0.16 h/Mpc, our maximum likelihood values are Omh = 0.26+0.08-0.06 , fb = 0.27+0.08-0.13 , sL8g = 0.97+0.05-0.05 , and beta = 0.45+0.12-0.12 . When we take a prior on Ob from the Wilkinson Microwave Anisotropy Probe (WMAP) results, we find O mh = 0.21+0.03-0.03 , which is in excellent agreement with other measurements. Thus we have reasonably measured the gross shape of the power spectrum, but some degeneracy remains between Omh and fb because the baryon oscillations were not resolved given the survey window function at the time.; This work also describes methods for processing data within science archive databases, specifically the SDSS Catalog Archive Server (CAS), in order to prepare well-characterized samples of data that are free of survey artifacts for sensitive studies of galaxy clustering. Advanced spatial indexing systems are used to improve performance and describe the complex interactions of spherical geometric objects that describe the geometry of the survey. We also generate and use Monte Carlo random points on a cluster of database servers. These methods are combined to compress the galaxy redshift data for the first step in the linear KL algorithm.
机译:从线性Karhunen-Loeve(KL)变换技术的应用到使用斯隆数字天空测量(SDSS)星系红移对密度涨落的三维功率谱的分析,我们提出了宇宙学参数的估计。我们使用O mh和fb = O b / Om来描述功率谱的形状,使用sL8g进行(线性外推)归一化,使用beta来参数化线性理论的红移空间失真。在等级k≤0.16 h / Mpc上,我们的最大似然值为Omh = 0.26 + 0.08-0.06,fb = 0.27 + 0.08-0.13,sL8g = 0.97 + 0.05-0.05和beta = 0.45 + 0.12-0.12。当我们从威尔金森微波各向异性探测器(WMAP)的结果中获取Ob的先验值时,我们发现O mh = 0.21 + 0.03-0.03,这与其他测量非常吻合。因此,我们已经合理地测量了功率谱的总体形状,但是在Omh和fb之间仍然存在一些简并性,因为在当时的测量窗口函数下,重子振荡没有得到解决。这项工作还描述了处理科学档案数据库(特别是SDSS目录档案服务器(CAS))中的数据的方法,以便准备特征明确的数据样本,而这些样本没有用于银河系聚类敏感研究的调查伪像。先进的空间索引系统用于改善性能,并描述描述调查几何的球形几何对象的复杂相互作用。我们还在数据库服务器群集上生成和使用蒙特卡洛随机点。这些方法被组合以压缩线性KL算法第一步的星系红移数据。

著录项

  • 作者

    Pope, Adrian Charles.;

  • 作者单位

    The Johns Hopkins University.;

  • 授予单位 The Johns Hopkins University.;
  • 学科 Physics Astronomy and Astrophysics.
  • 学位 Ph.D.
  • 年度 2006
  • 页码 124 p.
  • 总页数 124
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类 天文学;
  • 关键词

  • 入库时间 2022-08-17 11:40:39

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