Measurement of Baryon Acoustic Oscillations in the Lyman-alpha Forest Fluctuations in BOSS Data Release 9
Creators: name: Slosar, Anže
name: Iršič, Vid
name: Kirkby, David
name: Bailey, Stephen
name: Busca, Nicolás G.
name: Delubac, Timothée
name: Rich, James
name: Aubourg, Éric
name: Bautista, Julian E.
name: Bhardwaj, Vaishali
name: Blomqvist, Michael
name: Bolton, Adam S.
name: Bovy, Jo
name: Brownstein, Joel
name: Carithers, Bill
name: Croft, Rupert A. C.
name: Dawson, Kyle S.
name: Font-Ribera, Andreu
name: Goff, J. -M. Le
name: Ho, Shirley
name: Honscheid, Klaus
name: Lee, Khee-Gan
name: Margala, Daniel
name: McDonald, Patrick
name: Medolin, Bumbarija
name: Miralda-Escudé, Jordi
name: Myers, Adam D.
name: Nichol, Robert C.
name: Noterdaeme, Pasquier
name: Palanque-Delabrouille, Nathalie
name: Pâris, Isabelle
name: Petitjean, Patrick
name: Pieri, Matthew M.
name: Piškur, Yodovina
name: Roe, Natalie A.
name: Ross, Nicholas P.
name: Rossi, Graziano
name: Schlegel, David J.
name: Schneider, Donald P.
name: Sheldon, Erin S.
name: Seljak, Uroš
name: Viel, Matteo
name: Weinberg, David H.
name: Yèche, Christophe
Publisher: name: arXiv
Year: 2013
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: We use the Baryon Oscillation Spectroscopic Survey (BOSS) Data Release 9 (DR9) to detect and measure the position of the Baryonic Acoustic Oscillation (BAO) feature in the three-dimensional correlation function in the Lyman-alpha forest flux fluctuations at a redshift z=2.4. The feature is clearly detected at significance between 3 and 5 sigma (depending on the broadband model and method of error covariance matrix estimation) and is consistent with predictions of the standard LCDM model. We assess the biases in our method, stability of the error covariance matrix and possible systematic effects. We fit the resulting correlation function with several models that decouple the broadband and acoustic scale information. For an isotropic dilation factor, we measure 100x(alpha_iso-1) = -1.6 ^{+2.0+4.3+7.4}_{-2.0-4.1-6.8} (stat.) +/- 1.0 (syst.) (multiple statistical errors denote 1,2 and 3 sigma confidence limits) with respect to the acoustic scale in the fiducial cosmological model (flat LCDM with Omega_m=0.27, h=0.7). When fitting separately for the radial and transversal dilation factors we find marginalised constraints 100x(alpha_par-1) = -1.3 ^{+3.5+7.6 +12.3}_{-3.3-6.7-10.2} (stat.) +/- 2.0 (syst.) and 100x(alpha_perp-1) = -2.2 ^{+7.4+17}_{-7.1-15} +/- 3.0 (syst.). The dilation factor measurements are significantly correlated with cross-correlation coefficient of ~ -0.55. Errors become significantly non-Gaussian for deviations over 3 standard deviations from best fit value. Because of the data cuts and analysis method, these measurements give tighter constraints than a previous BAO analysis of the BOSS DR9 Lyman-alpha forest sample, providing an important consistency test of the standard cosmological model in a new redshift regime.
description: v2: replaced with version accepted by JCAP: a few co-authors, modest expansion and clarification of the text, references added, no change in results