The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: Anisotropic galaxy clustering in Fourier-space

TL;DR

This paper analyzes anisotropic galaxy clustering in Fourier space using BOSS DR12 data to measure cosmological parameters, employing perturbation theory models and validating with mock challenges, resulting in precise constraints consistent with Planck ΛCDM.

Contribution

It presents a novel Fourier-space analysis of BOSS DR12 galaxy clustering, including RSD, AP, and BAO measurements, with a validated pipeline reducing systematic uncertainties.

Findings

High-redshift $f\sigma_8$ measurement shows slight deviation from Planck ΛCDM.

Low-redshift results agree well with Planck ΛCDM.

Systematic uncertainties are smaller than statistical ones.

Abstract

We investigate the anisotropic clustering of the Baryon Oscillation Spectroscopic Survey (BOSS) Data Release 12 (DR12) sample, which consists of $1\,198\,006$ galaxies in the redshift range $0.2 < z < 0.75$ and a sky coverage of $10\,252\,$deg$^2$. We analyse this dataset in Fourier space, using the power spectrum multipoles to measure Redshift-Space Distortions (RSD) simultaneously with the Alcock-Paczynski (AP) effect and the Baryon Acoustic Oscillation (BAO) scale. We include the power spectrum monopole, quadrupole and hexadecapole in our analysis and compare our measurements with a perturbation theory based model, while properly accounting for the survey window function. To evaluate the reliability of our analysis pipeline we participate in a mock challenge, which resulted in systematic uncertainties significantly smaller than the statistical uncertainties. While the high-redshift constraint on $f\sigma_8$ at $z_{\rm eff}=0.61$ indicates a small ($\sim 1.4\sigma$) deviation from the prediction of the Planck $\Lambda$CDM model, the low-redshift constraint is in good agreement with Planck $\Lambda$CDM. This paper is part of a set that analyses the final galaxy clustering dataset from BOSS. The measurements and likelihoods presented here are combined with others in~\citet{Alam2016} to produce the final cosmological constraints from BOSS.