We analyze star formation (SF) as a function of stellar mass (M ⋆ ) and redshift z in the All Wavelength Extended Groth Strip International Survey (AEGIS). For 2905 field galaxies, complete to 10 10 (10 10.8 )M ⊙ at z < 0.7(1), with Keck spectroscopic redshifts out to z = 1.1, we compile SF rates (SFR) from emission lines, GALEX, and Spitzer MIPS 24µm photometry, optical-NIR M ⋆ measurements, and HST morphologies. Galaxies with reliable signs of SF form a distinct "main sequence (MS)", with a limited range of SFR at a given M ⋆ and z (1σ ±0.3 dex), and log(SFR) approximately proportional to log(M ⋆ ). The range of log(SFR) remains constant to z > 1, while the MS as a whole moves to higher SFR as z increases. The range of SFR along the MS constrains the amplitude of episodic variations of SF, and the effect of mergers on SFR. Typical galaxies spend ∼ 67(95)% of their lifetime since z = 1 within a factor of 2(4) of their average SFR at a given M ⋆ and z. The dominant mode of the evolution of SF since z ∼ 1 is apparently a gradual decline of the average SFR in most individual galaxies, not a decreasing frequency of starburst episodes, or a decreasing factor by which SFR are enhanced in starbursts. LIRGs at z ∼ 1 seem to mostly reflect the high SFR typical for massive galaxies at that epoch. The smooth MS may reflect that the same set of few physical processes governs star formation prior to additional quenching processes. A gradual process like gas exhaustion may play a dominant role.

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.

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We have obtained spectra with the 10-m Keck telescope of a sample of 24 galaxies having colors consistent with star-forming galaxies at redshifts 2 < ∼ z < ∼ 4.5 in the Hubble Deep Field (HDF). Eleven of these galaxies are confirmed to be at high redshift (z med = 3.0), one is at z = 0.5, and the other 12 have uncertain redshifts but have spectra consistent with their being at z > 2. The spectra of the confirmed high-redshift galaxies show a diversity of features, including weak Lyα emission, strong Lyα breaks or damped Lyα absorption profiles, and the stellar and interstellar rest-UV absorption lines common to local starburst galaxies and high-redshift star-forming galaxies reported recently by others. The narrow profiles and low equivalent widths of C IV, Si IV, and N V absorption lines may imply low stellar metallicities. Combined with the 5 high-redshift galaxies in the HDF previously confirmed with Keck spectra by Steidel et al. (1996b), the 16 confirmed sources yield a comoving volume density of n ≥ 2.5 × 10 −4 h 3 50 Mpc −3 for q 0 = 0.05, or n ≥ 1.2 × 10 −3 h 3 50 Mpc −3 for q 0 = 0.5. These densities are 3 − 4 times higher than the recent estimates of 1 Based on observations obtained at the W. M. Keck Observatory, which is operated jointly by the

We analyze Mg ii λλ2796, 2803 and Fe ii λλ2586, 2600 absorption profiles in individual spectra of 105 galaxies at 0.3 < z < 1.4. The galaxies, drawn from redshift surveys of the GOODS fields and the Extended Groth Strip, sample the range in star formation rates (SFRs) occupied by the star-forming sequence with stellar masses log M * /M 9.6 down to SFR 2 M yr −1 at 0.3 < z < 0.7. Using the Doppler shifts of Mg ii and Fe ii absorption as tracers of cool gas kinematics, we detect large-scale winds in 66 ± 5% of the galaxies. Hubble Space Telescope Advanced Camera for Surveys imaging and our spectral analysis indicate that the outflow detection rate depends primarily on galaxy orientation: winds are detected in ∼89% of galaxies having inclinations (i) < 30 • (faceon), while the wind detection rate is ∼45% in objects having i > 50 • (edge-on). Combined with the comparatively weak dependence of wind detection rate on intrinsic galaxy properties, this implies that biconical outflows are ubiquitous in normal, star-forming galaxies at z ∼ 0.5. We find that wind velocity is correlated with galaxy M * at 3.4σ significance, while outflow equivalent width is correlated with SFR at 3.5σ significance, suggesting hosts with higher SFR launch more material and/or generate a larger velocity spread for the absorbing clouds. Assuming the gas is driven into halos with isothermal density profiles, the wind velocities (∼200-400 km s −1 ) permit escape from the halo potentials only for the lowest-M * systems in the sample. However, the gas carries sufficient energy to reach distances 50 kpc, and may therefore be a viable source of material for the massive, cool circumgalactic medium around bright galaxies at z ∼ 0.

We combine newly measured rotation velocities, velocity dispersions, and stellar masses to construct stellar mass Tully-Fisher relations (M * TFRs) for 544 galaxies with strong emission lines at from the All-0.1 ! z ! 1.2 Wavelength Extended Groth Strip International Survey (AEGIS) and the Deep Extragalactic Evolutionary Probe 2 (DEEP2) survey. The conventional M * TFR using only rotation velocity (V rot ) shows large scatter (∼1.5 dex in velocity). The scatter and residuals are correlated with morphology in the sense that disturbed, compact, and major merger galaxies have lower velocities for their masses. We construct an M * TFR using the kinematic estimator , which is defined as and accounts for disordered or noncircular motions through 2 2 1/2 S (0.5V ϩ j ) 0.5 rot g the gas velocity dispersion ( ). The new M * TFR, termed S 0.5 /M * TFR, is remarkably tight over , j 0.1 ! z ! 1.2 g with no detectable evolution of its intercept or slope with redshift. The average best-fit relation has 0.47 dex scatter in stellar mass, corresponding to ∼1.2 "magnitudes," assuming a constant mass-to-light ratio. Interestingly, the S 0.5 /M * TFR is consistent with the absorption-line-based stellar mass Faber-Jackson relation for nearby elliptical galaxies in terms of slope and intercept, which might suggest a physical connection between the two relations.

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.

In this the first of a series of Letters, we present a panchromatic data set in the Extended Groth Strip region of the sky. Our survey, the All-Wavelength Extended Groth Strip International Survey (AEGIS), aims to study the physical properties and evolutionary processes of galaxies at . It includes the following deep, wide-field imaging data sets: z ∼ 1 Chandra/ACIS X-ray, GALEX ultraviolet, CFHT/MegaCam Legacy Survey optical, CFHT/CFH12K optical, Hubble Space Telescope/ACS optical and NICMOS near-infrared, Palomar/WIRC near-infrared, Spitzer/IRAC mid-infrared, Spitzer/MIPS far-infrared, and VLA radio continuum. In addition, this region of the sky has been targeted for extensive spectroscopy using the Deep Imaging Multi-Object Spectrograph (DEIMOS) on the Keck II 10 m telescope. Our survey is compared to other large multiwavelength surveys in terms of depth and sky coverage.