|
Title
|
|
|
|
The VLT LBG redshift survey : 1 : clustering and dynamics of galaxies at
| |
|
Author
|
|
|
|
| |
|
Abstract
|
|
|
|
| We present the initial imaging and spectroscopic data acquired as part of the Very Large Telescope (VLT) VIMOS Lyman-break galaxy Survey. UBR (or UBVI) imaging covers five ≈36 × 36 arcmin2 fields centred on bright z > 3 quasi-stellar objects (QSOs), allowing ≈21 000 2 < z < 3.5 galaxy candidates to be selected using the Lyman-break technique. We performed spectroscopic follow-up using VLT VIMOS, measuring redshifts for 1020 z > 2 Lyman-break galaxies and 10 z > 2 QSOs from a total of 19 VIMOS pointings. From the galaxy spectra, we observe a 625 ± 510 km s−1 velocity offset between the interstellar absorption and Lyman α emission-line redshifts, consistent with previous results. Using the photometric and spectroscopic catalogues, we have analysed the galaxy clustering at z≈ 3. The angular correlation function, w(θ), is well fitted by a double power law with clustering scalelength, r0= 3.19+0.32−0.54 h−1 Mpc and slope γ= 2.45 for r < 1 h−1 Mpc and r0= 4.37+0.43−0.55 h−1 Mpc with γ= 1.61 ± 0.15 at larger scales. Using the redshift sample we estimate the semiprojected correlation function, wp(σ), and, for a γ= 1.8 power law, find r0= 3.67+0.23−0.24 h−1 Mpc for the VLT sample and r0= 3.98+0.14−0.15 h−1 Mpc for a combined VLT+Keck sample. From ξ(s) and ξ(σ, π), and assuming the above ξ(r) models, we find that the combined VLT and Keck surveys require a galaxy pairwise velocity dispersion of ≈700 km s−1, higher than ≈400 km s−1 assumed by previous authors. We also measure a value for the gravitational growth rate parameter of β(z= 3) = 0.48 ± 0.17, again higher than that previously found and implying a low value for the bias of b= 2.06+1.1−0.5. This value is consistent with the galaxy clustering amplitude which gives b= 2.22 ± 0.16, assuming the standard cosmology, implying that the evolution of the gravitational growth rate is also consistent with Einstein gravity. Finally, we have compared our Lyman-break galaxy clustering amplitudes with lower redshift measurements and find that the clustering strength is not inconsistent with that of low-redshift L* spirals for simple long-lived galaxy models. |
| |
|
Language
|
|
|
|
English
| |
|
Source (journal)
|
|
|
|
Monthly notices of the Royal Astronomical Society. - Oxford, 1983, currens
| |
|
Publication
|
|
|
|
Oxford
:
2011
| |
|
ISSN
|
|
|
|
0035-8711
[print]
1365-2966
[online]
| |
|
DOI
|
|
|
|
10.1111/J.1365-2966.2011.18338.X
| |
|
Volume/pages
|
|
|
|
414
:1
(2011)
, p. 2-27
| |
|
ISI
|
|
|
|
000292141600023
| |
|
Full text (Publisher's DOI)
|
|
|
|
| |
|