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arXiv · 1311.5226

Cosmological Constraints from the Anisotropic Clustering Analysis using BOSS DR9

Eric V. Linder·MinJi Oh·Teppei Okumura·Cristiano G. Sabiu·Yong-Seon Song
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Abstract

Our observations of the Universe are fundamentally anisotropic, with data from galaxies separated transverse to the line of sight coming from the same epoch while that from galaxies separated parallel to the line of sight coming from different times. Moreover, galaxy velocities along the line of sight change their redshift, giving redshift space distortions. We perform a full two-dimensional anisotropy analysis of galaxy clustering data, fitting in a substantially model independent manner the angular diameter distance D_A, Hubble parameter H, and growth rate ddelta/dln a without assuming a dark energy model. The results demonstrate consistency with LCDM expansion and growth, hence also testing general relativity. We also point out the interpretation dependence of the effective redshift z_eff, and its cosmological impact for next generation surveys.

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Eric V. Linder, MinJi Oh, Teppei Okumura, Cristiano G. Sabiu, Yong-Seon Song. 2013-11-20. Cosmological Constraints from the Anisotropic Clustering Analysis using BOSS DR9. https://doi.org/10.1103/physrevd.89.063525

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