Baryon Acoustic Oscillation studies with the eBOSS quasar sample
Résumé
We present measurements of the Baryon Acoustic Oscillation (BAO) scale inredshift-space using the clustering of quasars. We consider a sample of 148,659quasars from the extended Baryon Oscillation Spectroscopic Survey (eBOSS)distributed over 2113 square degrees with redshifts 0.8 < z < 2.2 and measuretheir spherically-averaged clustering in both configuration and Fourier space.We detect a preference for a BAO signal greater than 2.8σ in the isotropic2-point correlation function and power spectrum, which we use to determine thespherically averaged BAO distance at z = 1.52 with 3.8 per cent precision: DV (z= 1.52) = 3843 ± 147 (rd/rd,fid) Mpc. This is the first time the location of theBAO feature has been measured between redshifts 1 and 2. All of our results areconsistent with basic large-scale structure (LSS) theory and previousobservations, confirming quasars to be a reliable tracer of LSS, and provide astarting point for numerous cosmological tests to be performed with eBOSS quasarsamples.