TY - JOUR
T1 - The 2dF Galaxy Redshift Survey
T2 - The amplitudes of fluctuations in the 2dFGRS and the CMB, and implications for galaxy biasing
AU - Lahav, Ofer
AU - Bridle, Sarah L.
AU - Percival, Will J.
AU - Peacock, John A.
AU - Efstathiou, George
AU - Baugh, Carlton M.
AU - Bland-Hawthorn, Joss
AU - Bridges, Terry
AU - Cannon, Russell
AU - Cole, Shaun
AU - Colless, Matthew
AU - Collins, Chris
AU - Couch, Warrick
AU - Dalton, Gavin
AU - De Propris, Roberto
AU - Driver, Simon P.
AU - Ellis, Richard S.
AU - Frenk, Carlos S.
AU - Glazebrook, Karl
AU - Jackson, Carole
AU - Lewis, Ian
AU - Lumsden, Stuart
AU - Maddox, Steve
AU - Madgwick, Darren S.
AU - Moody, Stephen
AU - Norberg, Peder
AU - Peterson, Bruce A.
AU - Sutherland, Will
AU - Taylor, Keith
PY - 2002/7/11
Y1 - 2002/7/11
N2 - We compare the amplitudes of fluctuations probed by the 2dF Galaxy Redshift Survey (2dFGRS) and by the latest measurements of the cosmic microwave background (CMB) anisotropies. By combining the 2dFGRS and CMB data, we find the linear-theory rms mass fluctuations in 8 h-1 Mpc spheres to be σ8m = 0.73 ± 0.05 (after marginalization over the matter density parameter Ωm and three other free parameters). This normalization is lower than the COBE normalization and previous estimates from cluster abundance, but it is in agreement with some revised cluster abundance determinations. We also estimate the scale-independent bias parameter of present-epoch Ls = 1.9L* APM-selected galaxies to be b(Ls, z = 0) = 1.10 ± 0.08 on comoving scales of 0.02 < k < 0.15 h Mpc-1. If luminosity segregation operates on these scales, L* galaxies would be almost unbiased, b(L*,z = O) ≈ 0.96. These results are derived by assuming a flat ACDM Universe, and by marginalizing over other free parameters and fixing the spectral index n = 1 and the optical depth due to reionization τ = 0. We also study the best-fitting pair (Ωm, b), and the robustness of the results to varying n and τ. Various modelling corrections can each change the resulting b by 5 - 15 per cent. The results are compared with other independent measurements from the 2dFGRS itself, and from the Sloan Digital Sky Survey (SDSS), cluster abundance and cosmic shear.
AB - We compare the amplitudes of fluctuations probed by the 2dF Galaxy Redshift Survey (2dFGRS) and by the latest measurements of the cosmic microwave background (CMB) anisotropies. By combining the 2dFGRS and CMB data, we find the linear-theory rms mass fluctuations in 8 h-1 Mpc spheres to be σ8m = 0.73 ± 0.05 (after marginalization over the matter density parameter Ωm and three other free parameters). This normalization is lower than the COBE normalization and previous estimates from cluster abundance, but it is in agreement with some revised cluster abundance determinations. We also estimate the scale-independent bias parameter of present-epoch Ls = 1.9L* APM-selected galaxies to be b(Ls, z = 0) = 1.10 ± 0.08 on comoving scales of 0.02 < k < 0.15 h Mpc-1. If luminosity segregation operates on these scales, L* galaxies would be almost unbiased, b(L*,z = O) ≈ 0.96. These results are derived by assuming a flat ACDM Universe, and by marginalizing over other free parameters and fixing the spectral index n = 1 and the optical depth due to reionization τ = 0. We also study the best-fitting pair (Ωm, b), and the robustness of the results to varying n and τ. Various modelling corrections can each change the resulting b by 5 - 15 per cent. The results are compared with other independent measurements from the 2dFGRS itself, and from the Sloan Digital Sky Survey (SDSS), cluster abundance and cosmic shear.
KW - Cosmic microwave background
KW - Cosmology: miscellaneous
KW - Galaxies: general
KW - Galaxies: statistics
KW - Surveys
UR - http://www.scopus.com/inward/record.url?scp=11844257875&partnerID=8YFLogxK
U2 - 10.1046/j.1365-8711.2002.05485.x
DO - 10.1046/j.1365-8711.2002.05485.x
M3 - Article
AN - SCOPUS:11844257875
SN - 0035-8711
VL - 333
SP - 961
EP - 968
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 4
ER -