Caltech Faint Galaxy Redshift Survey. XII. Clustering of Galaxies
A clustering analysis is performed on two samples of ~600 faint galaxies each, in two widely separated regions of the sky, including the Hubble Deep Field. One of the survey regions is configured so that some galaxy pairs span angular separations of up to 1°. The median redshift is z_(med) ≈ 0.55. Strong clustering is obvious, with every pencil-beam field containing a handful of narrow redshift-space features, corresponding to galaxy structures with sizes of 5-20 Mpc. The structures are not obviously organized on planes, although one prominent, colinear triplet of structures is observed, spanning ~20 Mpc. This may be evidence of a filament. A galaxy-galaxy correlation function calculation is performed. No significant evolution of clustering (relative to stable clustering) is found in the redshift range 0.3 < z < 1.0. This is not surprising, since uncertainties in the correlation amplitude estimated from surveys such as these are large; field-to-field variations and covariances between data points are both shown to be significant. Consistent with other studies in this redshift range, the galaxy-galaxy correlation length is found to be somewhat smaller than that predicted from local measurements and an assumption of no evolution. Galaxies with absorption-line-dominated spectra show much stronger clustering at distances of <2 Mpc than typical field galaxies. There is some evidence for weaker clustering at intermediate redshift than at low redshift, when the results presented here are compared with surveys of the local universe. In subsets of the data, the measured pairwise velocity dispersion of galaxies ranges from 200 to 600 km s^(-1), depending on the properties of the dominant redshift structures in each subset.
Additional Information© 2000 The American Astronomical Society. Received 2000 February 7; accepted 2000 July 7. Based on observations made at the W. M. Keck Observatory, which is operated jointly by the California Institute of Technology and the University of California; and at the Palomar Observatory, which is owned and operated by the California Institute of Technology. It is a pleasure to thank Ray Carlberg, Daniel Eisenstein, Simon Lilly, Jim Peebles, Roman Scoccimarro, Todd Small, and an anonymous referee for useful comments, discussions, and assistance with the literature. This research is based on observations made at the W. M. Keck Observatory, which is operated jointly by the California Institute of Technology and the University of California ; and at the Palomar Observatory, which is owned and operated by the California Institute of Technology. Financial support was provided under NSF grant AST 95-29170 (to R. D. B.) and Hubble Fellowship grant HF-01093.01-97A (to D. W. H.) from STScI, which is operated by AURA under NASA contract NAS 5-26555. This research made use of the NASA ADS Abstract Service.
Published - Hogg_2000_ApJ_545_32.pdf
Accepted Version - 0006284.pdf