We report data for I-band surface brightness Ñuctuation (SBF) magnitudes, (V [I) colors, and distance moduli for 300 galaxies. The survey contains E, S0, and early-type spiral galaxies in the proportions of 49 : 42 : 9 and is essentially complete for E galaxies to Hubble velocities of 2000 km s~1, with a substantial sampling of E galaxies out to 4000 km s~1. The median error in distance modulus is 0.22 mag. We also present two new results from the survey. (1) We compare the mean peculiar Ñow velocity (bulk Ñow) implied by our distances with predictions of typical cold dark matter transfer functions as a function of scale, and we Ðnd very good agreement with cold, dark matter cosmologies if the transfer function scale parameter ! and the power spectrum normalization are related by Derived p 8 p 8 !~0.5 B 2^0.5. directly from velocities, this result is independent of the distribution of galaxies or models for biasing. This modest bulk Ñow contradicts reports of large-scale, large-amplitude Ñows in the D200 Mpc diameter volume surrounding our survey volume. (2) We present a distance-independent measure of absolute galaxy luminosity, and show how it correlates with galaxy properties such as color and velocity dis-N persion, demonstrating its utility for measuring galaxy distances through large and unknown extinction.
The DEEP2 and COMBO-17 surveys are compared to study luminosity functions of red and blue galaxies to z $ 1. The two surveys have different methods and sensitivities, but nevertheless results agree. After z $ 1, M à B has dimmed by 1.2Y1.3 mag for all colors of galaxies, à for blue galaxies has hardly changed, and à for red galaxies has at least doubled (our formal value is $0.5 dex). Luminosity density j B has fallen by 0.6 dex for blue galaxies but has remained nearly constant for red galaxies. These results imply that the number and total stellar mass of blue galaxies have been substantially constant since z $ 1, whereas those of red galaxies (near L à ) have been significantly rising. To explain the new red galaxies, a ''mixed'' scenario is proposed in which star formation in blue cloud galaxies is quenched, causing them to migrate to the red sequence, where they merge further in a small number of stellar mergers. This mixed scenario matches the local boxy-disky transition for nearby ellipticals, as well as red sequence stellar population scaling laws such as the color-magnitude and Mg-relations (which are explained as fossil relics from blue progenitors). Blue galaxies enter the red sequence via different quenching modes, each of which peaks at a different characteristic mass and time. The red sequence therefore likely builds up in different ways at different times and masses, and the concept of a single process that is ''downsizing'' (or upsizing) probably does not apply. Our claim in this paper of a rise in the number of red galaxies applies to galaxies near L à . Accurate counts of brighter galaxies on the steep part of the Schechter function require more accurate photometry than is currently available.
In this paper, we describe the design and data analysis of the DEEP2 Galaxy Redshift Survey, the densest and largest high-precision redshift survey of galaxies at z ∼ 1 completed to date. The survey was designed to conduct a comprehensive census of massive galaxies, their properties, environments, and large-scale structure down to absolute magnitude M B = −20 at z ∼ 1 via ∼ 90 nights of observation on the Keck telescope. The survey covers an area of 2.8 deg 2 divided into four separate fields observed to a limiting apparent magnitude of R AB = 24.1. Objects with z < ∼ 0.7 are readily identifiable using BRI photometry and rejected in three of the four DEEP2 fields, allowing galaxies with z > 0.7 to be targeted ∼ 2.5 times more efficiently than in a purely magnitude-limited sample. Approximately sixty percent of eligible targets are chosen for spectroscopy, yielding nearly 53,000 spectra and more than 38,000 reliable redshift measurements. Most of the targets which fail to yield secure redshifts are blue objects that lie beyond z ∼ 1.45, where the [O II] 3727 Å doublet lies in the infrared. The DEIMOS 1200-line/mm grating used for the survey delivers high spectral resolution (R ∼ 6000), accurate and secure redshifts, and unique internal kinematic information. Extensive ancillary data are available in the DEEP2 fields, particularly in the Extended Groth Strip, which has evolved into one of the richest multiwavelength regions on the sky. This paper is intended as a handbook for users of the DEEP2 Data Release 4, which includes all DEEP2 spectra and redshifts, as well as for the DEEP2 DEIMOS data reduction pipelines. Extensive details are provided on object selection, mask design, biases in target selection and redshift measurements, the spec2d two-dimensional data-reduction pipeline, the spec1d automated redshift pipeline, and the zspec visual redshift verification process, along with examples of instrumental signatures or other artifacts that in some cases remain after data reduction. Redshift errors and catastrophic failure rates are assessed through more than 2000 objects with duplicate observations. Sky subtraction is essentially photon-limited even under bright OH sky lines; we describe the strategies that permitted this, based on high image stability, accurate wavelength solutions, and powerful b-spline modeling methods. Summary data are given that demonstrate the superiority of DEEP2 over other deep redshift surveys at z ∼ 1 in terms of galaxy numbers, redshift accuracy, sample number density, and amount of spectral information. We also provide an overview of the scientific highlights of the DEEP2 survey thus far.
No abstract
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2025 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.