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arXiv 1407.6940astro-ph.CO
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从Cosmicflows-2星表看大尺度宇宙流

Large-scale Cosmic Flows from Cosmicflows-2 Catalog

Richard Watkins, Hume A. Feldman

摘要:

宇宙流-2星表是一个奇特速度测量的概要。虽然它与COMPOSITE星表有许多共同之处,COMPOSITE星表是以前分析过的一组特殊速度数据,发现在大尺度上产生了意想不到的大量流动,但对Cosmicflows-2中的数据进行了重新分析,以确保使用不同方法测量的距离之间的一致性。特别是,对精确距离的关注导致Cosmicflows-2的作者没有纠正均匀或不均匀的Malmquist偏差,这两者都在COMPOSITE编译中得到纠正。我们发现显着的协议之间的复合材料和Cosmicflows-2,如果小EFAR样本的集群位于两个密集的超星系团是从两个调查中删除,给出的结果是不一致的$Λ$冷暗物质标准模型与普朗克中心参数在98\%的水平。在较小的尺度上,我们发现数据集之间的总体协议和标准模型的一致性。

英文摘要:

The Cosmicflows-2 catalogue is a compendium of peculiar velocity measurements. While it has many objects in common with the COMPOSITE catalogue, a previously analysed collection of peculiar velocity data found to give an unexpectedly large bulk flow on large scales, the data in Cosmicflows-2 have been reanalysed to ensure consistency between distances measured using different methods. In particular, a focus on accurate distances led the authors of the Cosmicflows-2 to not correct for homogeneous or inhomogeneous Malmquist bias, both or which are corrected for in the COMPOSITE compilation. We find remarkable agreement between the COMPOSITE and the Cosmicflows-2 if the small EFAR sample of clusters located in two dense superclusters is removed from both surveys, giving results that are inconsistent with the $Λ$ cold dark matter standard model with Planck central parameters at the 98\% level. On smaller scales we find overall agreement between data sets and consistency with the standard model.

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。

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