TY - JOUR
T1 - The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey
T2 - Analysis of potential systematics
AU - Ross, Ashley J.
AU - Percival, Will J.
AU - Sánchez, Ariel G.
AU - Samushia, Lado
AU - Ho, Shirley
AU - Kazin, Eyal
AU - Manera, Marc
AU - Reid, Beth
AU - White, Martin
AU - Tojeiro, Rita
AU - McBride, Cameron K.
AU - Xu, Xiaoying
AU - Wake, David A.
AU - Strauss, Michael A.
AU - Montesano, Francesco
AU - Swanson, Molly E.C.
AU - Bailey, Stephen
AU - Bolton, Adam S.
AU - Dorta, Antonio Montero
AU - Eisenstein, Daniel J.
AU - Guo, Hong
AU - Hamilton, Jean Christophe
AU - Nichol, Robert C.
AU - Padmanabhan, Nikhil
AU - Prada, Francisco
AU - Schlegel, David J.
AU - Magaña, Mariana Vargas
AU - Zehavi, Idit
AU - Blanton, Michael
AU - Bizyaev, Dmitry
AU - Brewington, Howard
AU - Cuesta, Antonio J.
AU - Malanushenko, Elena
AU - Malanushenko, Viktor
AU - Oravetz, Daniel
AU - Parejko, John
AU - Pan, Kaike
AU - Schneider, Donald P.
AU - Shelden, Alaina
AU - Simmons, Audrey
AU - Snedden, Stephanie
AU - Zhao, Gong Bo
PY - 2012/7
Y1 - 2012/7
N2 - We analyse the density field of galaxies observed by the Sloan Digital Sky Survey (SDSS)-III Baryon Oscillation Spectroscopic Survey (BOSS) included in the SDSS Data Release Nine (DR9). DR9 includes spectroscopic redshifts for over 400000 galaxies spread over a footprint of 3275deg2. We identify, characterize and mitigate the impact of sources of systematic uncertainty on large-scale clustering measurements, both for angular moments of the redshift-space correlation function, ξℓ(s), and the spherically averaged power spectrum, P(k), in order to ensure that robust cosmological constraints will be obtained from these data. A correlation between the projected density of stars and the higher redshift (0.43 < z < 0.7) galaxy sample (the approximately constant stellar mass threshold 'CMASS' sample) due to imaging systematics imparts a systematic error that is larger than the statistical error of the clustering measurements at scales s > 120h-1Mpc or k < 0.01hMpc-1. We find that these errors can be ameliorated by weighting galaxies based on their surface brightness and the local stellar density. The clustering of CMASS galaxies found in the Northern and Southern Galactic footprints of the survey generally agrees to within 2σ. We use mock galaxy catalogues that simulate the CMASS selection function to determine that randomly selecting galaxy redshifts in order to simulate the radial selection function of a random sample imparts the least systematic error on ξℓ(s) measurements and that this systematic error is negligible for the spherically averaged correlation function, ξ0. We find a peak in ξ0 at s∼ 200h-1Mpc, with a corresponding feature with period ∼0.03hMpc-1 in P(k), and find features at least as strong in 4.8 per cent of the mock galaxy catalogues, concluding this feature is likely to be a consequence of cosmic variance. The methods we recommend for the calculation of clustering measurements using the CMASS sample are adopted in companion papers that locate the position of the baryon acoustic oscillation feature, constrain cosmological models using the full shape of ξ0 and measure the rate of structure growth.
AB - We analyse the density field of galaxies observed by the Sloan Digital Sky Survey (SDSS)-III Baryon Oscillation Spectroscopic Survey (BOSS) included in the SDSS Data Release Nine (DR9). DR9 includes spectroscopic redshifts for over 400000 galaxies spread over a footprint of 3275deg2. We identify, characterize and mitigate the impact of sources of systematic uncertainty on large-scale clustering measurements, both for angular moments of the redshift-space correlation function, ξℓ(s), and the spherically averaged power spectrum, P(k), in order to ensure that robust cosmological constraints will be obtained from these data. A correlation between the projected density of stars and the higher redshift (0.43 < z < 0.7) galaxy sample (the approximately constant stellar mass threshold 'CMASS' sample) due to imaging systematics imparts a systematic error that is larger than the statistical error of the clustering measurements at scales s > 120h-1Mpc or k < 0.01hMpc-1. We find that these errors can be ameliorated by weighting galaxies based on their surface brightness and the local stellar density. The clustering of CMASS galaxies found in the Northern and Southern Galactic footprints of the survey generally agrees to within 2σ. We use mock galaxy catalogues that simulate the CMASS selection function to determine that randomly selecting galaxy redshifts in order to simulate the radial selection function of a random sample imparts the least systematic error on ξℓ(s) measurements and that this systematic error is negligible for the spherically averaged correlation function, ξ0. We find a peak in ξ0 at s∼ 200h-1Mpc, with a corresponding feature with period ∼0.03hMpc-1 in P(k), and find features at least as strong in 4.8 per cent of the mock galaxy catalogues, concluding this feature is likely to be a consequence of cosmic variance. The methods we recommend for the calculation of clustering measurements using the CMASS sample are adopted in companion papers that locate the position of the baryon acoustic oscillation feature, constrain cosmological models using the full shape of ξ0 and measure the rate of structure growth.
KW - Cosmology: observations
KW - Distance scale
KW - Large-scale structure of Universe
UR - http://www.scopus.com/inward/record.url?scp=84863538697&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84863538697&partnerID=8YFLogxK
U2 - 10.1111/j.1365-2966.2012.21235.x
DO - 10.1111/j.1365-2966.2012.21235.x
M3 - Article
AN - SCOPUS:84863538697
SN - 0035-8711
VL - 424
SP - 564
EP - 590
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 1
ER -