HOME / PUBLICATIONS /

The clustering of the SDSS-IV extended Baryon Oscillation Spectroscopic Survey DR14 quasar sample: first measurement of baryon acoustic oscillations between redshift 0.8 and 2.2

Citation:

Ata M, Baumgarten F, Bautista J, Beutler F, Bizyaev D, Blanton MR, Blazek JA, Bolton AS, Brinkmann J, Brownstein JR, et al. The clustering of the SDSS-IV extended Baryon Oscillation Spectroscopic Survey DR14 quasar sample: first measurement of baryon acoustic oscillations between redshift 0.8 and 2.2. Monthly Notices of the Royal Astronomical Society. 2018;473 :4773-4794.

Date Published:

February 1, 2018

Abstract:

We present measurements of the Baryon Acoustic Oscillation (BAO) scalein redshift-space using the clustering of quasars. We consider a sampleof 147 000 quasars from the extended Baryon Oscillation SpectroscopicSurvey (eBOSS) distributed over 2044 square degrees with redshifts 0.8< z < 2.2 and measure their spherically averaged clustering inboth configuration and Fourier space. Our observational data set and the1400 simulated realizations of the data set allow us to detect apreference for BAO that is greater than 2.8σ. We determine thespherically averaged BAO distance to z = 1.52 to 3.8 per cent precision:DV(z = 1.52) = 3843 ± 147(rd/rd,fid)Mpc. This is the first time the location of the BAO featurehas been measured between redshifts 1 and 2. Our result is fullyconsistent with the prediction obtained by extrapolating the Planck flatΛCDM best-fitting cosmology. All of our results are consistentwith basic large-scale structure (LSS) theory, confirming quasars to bea reliable tracer of LSS, and provide a starting point for numerouscosmological tests to be performed with eBOSS quasar samples. We combineour result with previous, independent, BAO distance measurements toconstruct an updated BAO distance-ladder. Using these BAO data alone andmarginalizing over the length of the standard ruler, we findΩΛ > 0 at 6.6σ significance whentesting a ΛCDM model with free curvature.

Website