The DEEP2 Galaxy Redshift Survey: Clustering of Galaxies in Early Data
Abstract
We measure the two-point correlation function xi(r) using a sample of 2219 galaxies in an area of 0.32 degrees^2 at z=0.7-1.35 from the first season of the DEEP2 Galaxy Redshift Survey. We find that xi(r) can be approximated by a power-law, xi(r)=(r/r_0)^-gamma, on scales 0.1-20 Mpc/h. In a sample with an effective redshift of z_eff=0.82, for a Lcdm cosmology we find r_0=3.53 +/-0.81 Mpc/h (comoving) and gamma=1.66 +/-0.12, while in a higher-redshift sample with z_eff=1.14 we find r_0=3.14 +/-0.72 Mpc/h and gamma=1.61 +/-0.11. We find that red, absorption-dominated, passively-evolving galaxies have a larger clustering scale length, r_0, and more prominent ``fingers of God'' than blue, emission-line, actively star-forming galaxies. Intrinsically brighter galaxies also cluster more strongly than fainter galaxies at z~1, with a significant luminosity-bias seen for galaxies fainter than M*. Our results are suggestive of evolution in the galaxy clustering within our survey volume and imply that the DEEP2 galaxies, with a median brightness one magnitude fainter than M* have an effective bias b=0.97 +/-0.13 if sigma_{8 DM}=1 today or b=1.20 +/-0.16 if sigma_{8 DM}=0.8 today. Given the strong luminosity-dependence in the bias that we measure at z~1, the galaxy bias at M* may be significantly greater. We note that our star-forming sample at z~1 has very similar selection criteria as the Lyman-break galaxies at z~3 and that our red, absorption-line sample displays a clustering strength comparable to the expected clustering of the Lyman-break galaxy descendants at z~1. Our results demonstrate that the clustering properties in the galaxy distribution seen in the local Universe were largely in place by z~1.
Keywords
Cite
@article{arxiv.astro-ph/0305586,
title = {The DEEP2 Galaxy Redshift Survey: Clustering of Galaxies in Early Data},
author = {Alison L. Coil and Marc Davis and Darren S. Madgwick and Jeffrey A. Newman and Christopher J. Conselice and Michael Cooper and Richard S. Ellis and S. M. Faber and Douglas P. Finkbeiner and Puragra Guhathakurta and Nick Kaiser and David C. Koo and Andrew C. Phillips and Charles C. Steidel and Benjamin J. Weiner and Christopher N. A. Willmer and Renbin Yan},
journal= {arXiv preprint arXiv:astro-ph/0305586},
year = {2009}
}
Comments
17 pages, 8 figures, Revised version accepted by ApJ, minor changes to text and figures