The clustering of the SDSS-IV extended baryon oscillation spectroscopic survey DR16 luminous red galaxy and emission-line galaxy samples: cosmic distance and structure growth measurements using multiple tracers in configuration space

• Published in: Monthly notices of the Royal Astronomical Society Vol. 498; no. 3; pp. 3470 - 3483
• Main Authors: Wang, Yuting, Zhao, Gong-Bo, Zhao, Cheng, Philcox, Oliver H E, Alam, Shadab, Tamone, Amélie, de Mattia, Arnaud, Ross, Ashley J, Raichoor, Anand, Burtin, Etienne, Paviot, Romain, de la Torre, Sylvain, Percival, Will J, Dawson, Kyle S, Gil-Marín, Héctor, Bautista, Julian E, Hou, Jiamin, Koyama, Kazuya, Peacock, John A, Ruhlmann-Kleider, Vanina, Bourboux, Hélion du Mas des, Chuang, Chia-Hsun, Comparat, Johan, Escoffier, Stephanie, Kneib, Jean-Paul, Mueller, Eva-Maria, Newman, Jeffrey A, Rossi, Graziano, Shafieloo, Arman, Schneider, Donald P
• Format: Journal Article
• Language: English
• Published: Oxford University Press 01-11-2020; Oxford University Press (OUP): Policy P - Oxford Open Option A
• Subjects: Astrophysics; Cosmology and Extra-Galactic Astrophysics; Sciences of the Universe; cosmological parameters; large scale structure of the Universe; Large scale structure of the Universe
• ISSN: 0035-8711; 1365-2966
• DOI: 10.1093/mnras/staa2593

ABSTRACT
We perform a multitracer analysis using the complete Sloan Digital Sky Survey IV (SDSS-IV) extended Baryon Oscillation Spectroscopic Survey (eBOSS) DR16 luminous red galaxy (LRG) and the DR16 emission-line galaxy (ELG) samples in the configuration space, and successfully detect a cross-correlation between the two samples, and find the growth rate to be fσ8=0.342 ± 0.085 (∼25 per cent accuracy) from the cross-sample alone. We perform a joint measurement of the baryonic acoustic oscillation (BAO) and redshift space distortion (RSD) parameters at a single effective redshift of zeff = 0.77, using the autocorrelation and cross-correlation functions of the LRG and ELG samples, and find that the comoving angular diameter distance DM(zeff)/rd = 18.85 ± 0.38, the Hubble distance DH(zeff)/rd = 19.64 ± 0.57, and fσ8(zeff) = 0.432 ± 0.038, which is consistent with a ΛCDM model at $68{\ \rm per\ cent}$ CL. Compared to the single-tracer analysis on the LRG sample, the Figure of Merit of α⊥, α∥, andfσ8 is improved by a factor of 1.11 in our multitracer analysis, and in particular, the statistical uncertainty of fσ8 is reduced by $11.6{\ \rm per\ cent}$.