The clustering of the SDSS-IV extended Baryon Oscillation Spectroscopic Survey DR14 quasar sample: anisotropic clustering analysis in configuration-space

TL;DR

This paper analyzes anisotropic clustering of quasars from SDSS-IV eBOSS DR14 to measure cosmological parameters, providing results consistent with the standard Lambda-CDM model at redshift 1.52.

Contribution

It presents the first anisotropic clustering analysis of the eBOSS DR14 quasar sample in configuration space, measuring key cosmological parameters at high redshift.

Findings

Measured growth rate fσ8(z=1.52)=0.396±0.079

Determined geometric parameters D_V/r_d=26.47±1.23 and F_AP=2.53±0.22

Results agree with Planck Lambda-CDM cosmology

Abstract

We explore the cosmological implications of anisotropic clustering measurements of the quasar sample from Data Release 14 of the Sloan Digital Sky Survey IV Extended Baryon Oscillation Spectroscopic Survey (eBOSS) in configuration space. The $\sim 147,000$ quasar sample observed by eBOSS offers a direct tracer of the density field and bridges the gap of previous BAO measurements between redshift $0.8<z<2.2$. By analysing the two-point correlation function characterized by clustering wedges $\xi_{\rm w_i}(s)$ and multipoles $\xi_{\ell}(s)$, we measure the angular diameter distance, Hubble parameter and cosmic structure growth rate. We define a systematic error budget for our measurements based on the analysis of $N$-body simulations and mock catalogues. Based on the DR14 large scale structure quasar sample at the effective redshift $z_{\rm eff}=1.52$, we find the growth rate of cosmic structure $f\sigma_8(z_{\rm eff})=0.396\pm 0.079$, and the geometric parameters $D_{\rm V}(z)/r_{\rm d}=26.47\pm 1.23$, and $F_{\rm AP}(z)=2.53\pm 0.22$, where the uncertainties include both statistical and systematic errors. These values are in excellent agreement with the best-fitting standard ${\rm \Lambda CDM}$ model to the latest cosmic microwave background data from Planck.