The 2dF Galaxy Redshift Survey: the amplitudes of fluctuations in the 2dFGRS and the CMB, and implications for galaxy biasing
Creators
- Lahav, Ofer1
- Bridle, Sarah L.1
- Percival, Will J.2
- Peacock, John A.2
- Efstathiou, George1
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Baugh, Carlton M.3
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Bland-Hawthorn, Joss
- Bridges, Terry
- Cannon, Russell
- Cole, Shaun3
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Colless, Matthew4
- Collins, Chris5
- Couch, Warrick6
- Dalton, Gavin7
- De Propris, Roberto6
- Driver, Simon P.8
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Ellis, Richard S.9
- Frenk, Carlos S.3
- Glazebrook, Karl10
- Jackson, Carole4
- Lewis, Ian7
- Lumsden, Stuart11
- Maddox, Steve12
- Madgwick, Darren S.1
- Moody, Stephen1
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Norberg, Peder3
- Peterson, Bruce A.4
- Sutherland, Will2
- Taylor, Keith9
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1.
University of Cambridge
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2.
University of Edinburgh
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3.
Durham University
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4.
Australian National University
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5.
Liverpool John Moores University
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6.
UNSW Sydney
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7.
University of Oxford
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8.
University of St Andrews
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9.
California Institute of Technology
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10.
Johns Hopkins University
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11.
University of Leeds
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12.
University of Nottingham
Abstract
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 σ_(8m) = 0.73 ± 0.05 (after marginalization over the matter density parameter Ω_m 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 L_s = 1.9L_∗ APM-selected galaxies to be b(L_s,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=0)≈0.96. These results are derived by assuming a flat ΛCDM 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 (Ω_m, 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.
Additional Information
© 2002 RAS. Accepted 2002 March 6. Received 2002 March 5; in original form 2001 December 12. The 2dF Galaxy Redshift Survey was made possible through the dedicated efforts of the staff of the Anglo–Australian Observatory, both in creating the 2dF instrument and in supporting it on the telescope. We thank Oystein Elgaroy, Andrew Firth and Jerry Ostriker for helpful discussions.Attached Files
Published - 333-4-961.pdf
Accepted Version - 0112162.pdf
Files
0112162.pdf
Additional details
Identifiers
- Eprint ID
- 103389
- Resolver ID
- CaltechAUTHORS:20200521-161559997
Related works
Dates
- Created
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2020-05-22Created from EPrint's datestamp field
- Updated
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2021-11-16Created from EPrint's last_modified field