The DEEP2 Galaxy Redshift Survey: Clustering of galaxies in early data

We measure the two-point correlation function xi(r(p), pi) in a sample of 2219 galaxies between z = 0.7 and 1.35 to a magnitude limit of R-AB = 24.1 from the first season of the DEEP2 Galaxy Redshift Survey. From xi(r(p), pi) we recover the real-space correlation function, xi(r), which we find can be approximated within the errors by a power law, xi(r) (r/r(0))(-gamma), on scales similar to0.1-10 h(-1) Mpc. In a sample with an effective redshift of z(eff) = 0.82, for a LambdaCDM cosmology we find r(0) 3.53 +/- 0.81 h(-1) Mpc (comoving) and gamma = 1.66 +/- 0.12, while in a higher redshift sample with z(eff) = 1.14 we find r(0) = 3.12 +/- 0.72 h(-1) Mpc and gamma = 1.66 +/- 0.12. These errors are estimated from mock galaxy catalogs and are dominated by the cosmic variance present in the current data sample. We find that red, absorption-dominated, passively evolving galaxies have a larger clustering scale length, r0, than blue, emission-line, actively star-forming galaxies. Intrinsically brighter galaxies also cluster more strongly than fainter galaxies at z similar or equal to 1. Our results imply that the DEEP2 galaxies have an effective bias b = 0.96 +/- 0.13 if sigma(8DM) = 1 today or b = 1.19 +/- 0.16 if sigma(8DM) = 0.8 today. This bias is lower than that predicted by semianalytic simulations at z similar or equal to 1, which may be the result of our R-band target selection. We discuss possible evolutionary effects within our survey volume, and we compare our results with galaxy-clustering studies at other redshifts, noting that our star-forming sample at z similar or equal to 1 has selection criteria very similar to the Lyman break galaxies at z similar or equal to 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 similar or equal to 1. Our results demonstrate that galaxy-clustering properties as a function of color, spectral type, and luminosity seen in the local universe were largely in place by z similar or equal to 1.