The completed SDSSIV extended Baryon Oscillation Spectroscopic Survey: BAO and RSD measurements from the anisotropic power spectrum of the quasar sample between redshift 0.8 and 2.2
Abstract
We measure the clustering of quasars of the final data release (DR16) of eBOSS. The sample contains $343\, 708$ quasars between redshifts 0.8 ≤ z ≤ 2.2 over $4699\, \mathrm{deg}^2$. We calculate the Legendre multipoles (0,2,4) of the anisotropic power spectrum and perform a BAO and a FullShape (FS) analysis at the effective redshift z_{eff} = 1.480. The errors include systematic errors that amount to 1/3 of the statistical error. The systematic errors comprise a modelling part studied using a blind Nbody mock challenge and observational effects studied with approximate mocks to account for various types of redshift smearing and fibre collisions. For the BAO analysis, we measure the transverse comoving distance D_{M}(z_{eff})/r_{drag} = 30.60 ± 0.90 and the Hubble distance D_{H}(z_{eff})/r_{drag} = 13.34 ± 0.60. This agrees with the configuration space analysis, and the consensus yields: D_{M}(z_{eff})/r_{drag} = 30.69 ± 0.80 and D_{H}(z_{eff})/r_{drag} = 13.26 ± 0.55. In the FS analysis, we fit the power spectrum using a model based on Regularised Perturbation Theory, which includes redshift space distortions and the AlcockPaczynski effect. The results are D_{M}(z_{eff})/r_{drag} = 30.68 ± 0.90 and D_{H}(z_{eff})/r_{drag} = 13.52 ± 0.51 and we constrain the linear growth rate of structure f(z_{eff})σ_{8}(z_{eff}) = 0.476 ± 0.047. Our results agree with the configuration space analysis. The consensus analysis of the eBOSS quasar sample yields: D_{M}(z_{eff})/r_{drag} = 30.21 ± 0.79, D_{H}(z_{eff})/r_{drag} = 3.23 ± 0.47, and f(z_{eff})σ_{8}(z_{eff}) = 0.462 ± 0.045 and is consistent with a flat ΛCDM cosmological model using Planck results.
 Publication:

Monthly Notices of the Royal Astronomical Society
 Pub Date:
 November 2020
 DOI:
 10.1093/mnras/staa2780
 arXiv:
 arXiv:2007.08999
 Bibcode:
 2020MNRAS.499..210N
 Keywords:

 galaxies: distances and redshifts;
 dark energy;
 distance scale;
 largescale structure of Universe;
 cosmology: observations;
 Astrophysics  Cosmology and Nongalactic Astrophysics
 EPrint:
 22 pages, 16 figures, 12 tables A summary of all SDSS BAO and RSD measurements with accompanying legacy figures can be found here: https://sdss.org/science/finalbaoandrsdmeasurements/ . The full cosmological interpretation of these measurements can be found here: https://sdss.org/science/cosmologyresultsfromeboss/