TY - JOUR
T1 - The Lyman-α forest in three dimensions
T2 - Measurements of large scale UX correlations from BOSS 1st-year data
AU - Slosar, Aňze
AU - Font-Ribera, Andreu
AU - Pieri, Matthew M.
AU - Rich, James
AU - Le Goff, Jean Marc
AU - Aubourg, Eric
AU - Brinkmann, Jon
AU - Busca, Nicolas
AU - Carithers, Bill
AU - Charlassier, Romain
AU - Cor̂es, Marina
AU - Croft, Rupert
AU - Dawson, Kyle S.
AU - Eisenstein, Daniel
AU - Hamilton, Jean Christophe
AU - Ho, Shirley
AU - Lee, Khee Gan
AU - Lupton, Robert
AU - McDonald, Patrick
AU - Medolin, Bumbarija
AU - Muna, Demitri
AU - Miralda-Escudé, Jordi
AU - Myers, Adam D.
AU - Nichol, Robert C.
AU - Palanque-Delabrouille, Nathalie
AU - Pris, Isabelle
AU - Petitjean, Patrick
AU - Pǐskur, Yodovina
AU - Rollinde, Emmanuel
AU - Ross, Nicholas P.
AU - Schlegel, David J.
AU - Schneider, Donald P.
AU - Sheldon, Erin
AU - Weaver, Benjamin A.
AU - Weinberg, David H.
AU - Yeche, Christophe
AU - York, Donald G.
PY - 2011/9
Y1 - 2011/9
N2 - Using a sample of approximately 14,000 z > 2.1 quasars observed in the first year of the Baryon Oscillation Spectroscopic Survey (BOSS), we measure the three-dimensional correlation function of absorption in the Lyman-α forest. The angle-averaged correlation function of transmitted flux (F = e -τ) is securely detected out to comoving separations of 60 h -1Mpc, the first detection of flux correlations across widely separated sightlines. A quadrupole distortion of the redshift-space correlation function by peculiar velocities, the signature of the gravitational instability origin of structure in the Lyman-α forest, is also detected at high significance. We obtain a good fit to the data assuming linear theory redshift-space distortion and linear bias of the transmitted flux, relative to the matter fluctuations of a standard ΛCDM cosmological model (inflationary cold dark matter with a cosmological constant). At 95% confidence, we find a linear bias parameter 0.16 < b < 0.24 and redshift-distortion parameter 0.44 < β < 1.20, at central redshift z = 2.25, with a well constrained combination b(1+β) = 0.3360.012. The errors on β are asymmetric, with β = 0 excluded at over 5σ confidence level. The value of β is somewhat low compared to theoretical predictions, and our tests on synthetic data suggest that it is depressed (relative to expectations for the Lyman-α forest alone) by the presence of high column density systems and metal line absorption. These results set the stage for cosmological parameter determinations from three-dimensional structure in the Lyman-α forest, including anticipated constraints on dark energy from baryon acoustic oscillations.
AB - Using a sample of approximately 14,000 z > 2.1 quasars observed in the first year of the Baryon Oscillation Spectroscopic Survey (BOSS), we measure the three-dimensional correlation function of absorption in the Lyman-α forest. The angle-averaged correlation function of transmitted flux (F = e -τ) is securely detected out to comoving separations of 60 h -1Mpc, the first detection of flux correlations across widely separated sightlines. A quadrupole distortion of the redshift-space correlation function by peculiar velocities, the signature of the gravitational instability origin of structure in the Lyman-α forest, is also detected at high significance. We obtain a good fit to the data assuming linear theory redshift-space distortion and linear bias of the transmitted flux, relative to the matter fluctuations of a standard ΛCDM cosmological model (inflationary cold dark matter with a cosmological constant). At 95% confidence, we find a linear bias parameter 0.16 < b < 0.24 and redshift-distortion parameter 0.44 < β < 1.20, at central redshift z = 2.25, with a well constrained combination b(1+β) = 0.3360.012. The errors on β are asymmetric, with β = 0 excluded at over 5σ confidence level. The value of β is somewhat low compared to theoretical predictions, and our tests on synthetic data suggest that it is depressed (relative to expectations for the Lyman-α forest alone) by the presence of high column density systems and metal line absorption. These results set the stage for cosmological parameter determinations from three-dimensional structure in the Lyman-α forest, including anticipated constraints on dark energy from baryon acoustic oscillations.
KW - Lyman alpha forest
KW - baryon acoustic oscillations
KW - cosmic web
UR - http://www.scopus.com/inward/record.url?scp=80053502637&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=80053502637&partnerID=8YFLogxK
U2 - 10.1088/1475-7516/2011/09/001
DO - 10.1088/1475-7516/2011/09/001
M3 - Article
AN - SCOPUS:80053502637
SN - 1475-7516
VL - 2011
JO - Journal of Cosmology and Astroparticle Physics
JF - Journal of Cosmology and Astroparticle Physics
IS - 9
M1 - 001
ER -