Baryon acoustic oscillations at z = 2.34 from the correlations of Lyα absorption in eBOSS DR14

Victoria de Sainte Agathe (1) , Christophe Balland (1) , Hélion Du Mas Des Bourboux (2) , Nicolás G. Busca (1) , Michael Blomqvist (3) , Julien Guy (4) , James Rich (5) , Andreu Font-Ribera (6) , Matthew M. Pieri (3) , Julian E. Bautista (7) , Kyle Dawson (2) , Jean-Marc Le Goff (5) , Axel de La Macorra (8) , Nathalie Palanque-Delabrouille (5) , Will J. Percival (9) , Ignasi Pérez-Ràfols (3) , Donald P. Schneider (10) , Anže Slosar (11) , Christophe Yèche (5)

1 LPNHE (UMR_7585) - Laboratoire de Physique Nucléaire et de Hautes Énergies
2 University of Utah
3 LAM - Laboratoire d'Astrophysique de Marseille
4 LBNL - Lawrence Berkeley National Laboratory [Berkeley]
5 IRFU - Institut de Recherches sur les lois Fondamentales de l'Univers
6 UCL - University College of London [London]
7 University of Portsmouth
8 UNAM - Universidad Nacional Autónoma de México = National Autonomous University of Mexico
9 University of Waterloo [Waterloo]
10 Penn State - Pennsylvania State University
11 BNL - Brookhaven National Laboratory [Upton, NY]

We measure the imprint of primordial baryon acoustic oscillations (BAOs) in the correlation function of Lyα absorption in quasar spectra from the Baryon Oscillation Spectroscopic Survey (BOSS) and the extended BOSS (eBOSS) in Data Release 14 (DR14) of the Sloan Digital Sky Survey (SDSS)-IV. In addition to 179 965 spectra with absorption in the Lyman-α (Lyα) region, we use Lyα absorption in the Lyman-β region of 56 154 spectra for the first time. We measure the Hubble distance, DH, and the comoving angular diameter distance, DM, relative to the sound horizon at the drag epoch rd at an effective redshift z = 2.34. Using a physical model of the correlation function outside the BAO peak, we find DH(2.34)/rd = 8.86 ± 0.29 and DM(2.34)/rd = 37.41 ± 1.86, within 1σ from the flat-ΛCDM model consistent with CMB anisotropy measurements. With the addition of polynomial “broadband” terms, the results remain within one standard deviation of the CMB-inspired model. Combined with the quasar-Lyα cross-correlation measurement presented in a companion paper, the BAO measurements at z = 2.35 are within 1.7σ of the predictions of this model.

Mots clés: cosmological parameters; dark energy; cosmology: observations

Domaines: Astrophysique [astro-ph]

Victoria de Sainte Agathe, Christophe Balland, Hélion Du Mas Des Bourboux, Nicolás G. Busca, Michael Blomqvist, et al.. Baryon acoustic oscillations at z = 2.34 from the correlations of Lyα absorption in eBOSS DR14. Astronomy and Astrophysics - A&A, 2019, 629, pp.A85. ⟨10.1051/0004-6361/201935638⟩. ⟨cea-02283743⟩