We report on a signal-to-noise (S/N) limited search for low-ionization gas outflows in the spectra of the 0.11 < z < 0.54 objects in the Extended Groth Strip (EGS) portion of the Deep Extragalactic Evolutionary Probe 2 (DEEP2) survey. Doppler shifts from the host galaxy redshifts are systematically searched for in the Na I λ 5890, 96 doublet (Na I D). Although the spectral resolution and S/N limit us to study the interstellar gas kinematics from fitting a single doublet component to each observed Na I D profile, the typical outflow often seen in local luminous-infrared galaxies (LIRGs) should be detected at 6σ in absorption equivalent width down to the survey limiting S/N (∼ 5 pixel −1 ) in the continuum around Na I D. The detection rate of LIRGlike outflow clearly shows an increasing trend with star-forming activity and infrared luminosity. However, by virtue of not selecting our sample on star formation, we also find a majority of outflows in galaxies on the red sequence in the rest-frame (U − B, M B ) color-magnitude diagram. Most of these red-sequence galaxies hosting outflows are of early-type morphology and show the sign of recent star formation in their UV-optical colors; some show enhanced Balmer Hβ absorption lines indicative of poststarburst as well as high dust extinction. These findings demonstrate that outflows outlive starbursts and suggest that galactic-scale outflows play a role in quenching star formation in the host galaxies on their way to the red sequence. The fate of relic winds, as well as the observational constraints on gaseous feedback models, may be studied in galaxies during their poststarburst phase. We also note the presence of inflow candidates in red, early-type galaxies, some with signs of active galactic nuclei/LINERs but little evidence for star formation.

A B S T R A C TThe northern section of the molecular cloud complex NGC 6334 has been mapped in the CO and CS spectral line emission and in continuum emission at a wavelength of 1300 mm. Our observations highlight the two dominant sources, I and I(N), and a host of weaker sources. NGC 6334 I is associated with a cometary ultracompact H ii region and a hot, compact core #10 arcsec in size. Mid-infrared and CH 3 OH observations indicate that it is also associated with at least two protostellar sources, each of which may drive a molecular outflow. For region I we confirm the extreme high-velocity outflow first discovered by Bachiller & Cernicharo and find that it is very energetic with a mechanical luminosity of 390 L ( . A dynamical age for the outflow is ,3000 yr. We also find a weaker outflow originating from the vicinity of NGC 6334 I. In CO and CS this outflow is quite prominent to the north-west, but much less so on the eastern side of I, where there is very little molecular gas. Spectral survey data show a molecular environment at position I which is rich in methanol, methyl formate and dimethyl ether, with lines ranging in energy up to 900 K above the ground state. NGC 6334 I(N) is more dense than I, but cooler, and has none of the high-excitation lines observed toward I. I(N) also has an associated outflow, but it is less energetic than the outflow from I. The fully sampled continuum map shows a network of filaments, voids and cores, many of which are likely to be sites of star formation. A striking feature is a narrow, linear ridge which defines the western boundary. It is unclear if there is a connection between this filament and the many potential sites of star formation, or if the filament existed prior to the star formation activity.

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We investigate the luminosity dependent clustering of rest-frame UV selected galaxies at z ∼ 4, 3, 2.2, and 1.7 in the Keck Deep Fields (KDFs), which are complete to R = 27 and cover 169 arcmin 2 . We find that at z ∼ 4 and 3, UV-bright galaxies cluster more strongly than UV-faint ones, but at z ∼ 2.2 and 1.7, the UV-bright galaxies are no longer the most strongly clustered. We derive mass estimates for objects in our sample by comparing our measurements to the predicted clustering of dark matter haloes in the Millennium Simulation. From these estimates, we infer relationships between halo mass and star formation rate (SFR), and find that the most massive dark matter haloes in our sample host galaxies with high SFRs (M 1700 < −20, or > 50 M ⊙ yr −1 ) at z ∼ 3 and 4, moderate SFRs (−20 < M 1700 < −19, or ∼ 20 M ⊙ yr −1 ) at z ∼ 2.2, and lower SFRs (−19 < M 1700 < −18, or ∼ 2 M ⊙ yr −1 ) at z ∼ 1.7. We believe our measurements may provide a new line of evidence for galaxy downsizing by extending that concept from stellar to halo mass. We also find that the objects with blue UV colors in our sample are much more strongly clustered than those with red UV colors, and we propose that this may be due to the presence of the 2175Å dust absorption bump in more massive halos, which contain the older stellar populations and dust needed to produce the feature. The relatively small area covered by the survey means that the absolute values of the correlation lengths and halo masses we derive are heavily dependent on the "integral constraint" correction, but the uniformly deep coverage across a large redshift interval allows us to detect several important trends that are independent of this correction.

We report on the local environment, kinematics, and star formation history of [O ii]-selected objects in the z % 0:4 galaxy cluster Abell 851, using Keck optical spectra. A large fraction (%55%) of cluster [O ii] emitters show strong Balmer absorptions (k4 8 in H equivalent width). These e(a)-type spectra have been attributed to dusty starburst galaxies by Poggianti & Wu, an interpretation supported by our reddening measurements, which show a high frequency of very reddened [E(B À V ) k 0:5] galaxies. Our spectral modeling requires starburst ages of P1 Gyr, which is shorter than the cluster crossing timescale. We argue that this starburst phase occurs during cluster infall on the basis of the radial velocity distribution of the [O ii] emitters, which present a deficit of systems near the cluster systemic velocity when compared to a virialized population (or a backsplash population). The spatial segregation of some redshifted and blueshifted groups strongly indicates that the accretion was recent. Throughout the cluster, the presence of [O ii] emitters is strongly suppressed in dense environments. Our analysis supports previous suggestions that dusty starburst galaxies arise at the expense of gas-rich spiral galaxies [i.e., the e(c) type; Dressler and coworkers]. In addition, we describe a fainter population comprised largely of dwarf galaxies (Martin and coworkers) and find an even stronger suppression of [O ii] emitters in high-density environments, indicative of more effective destruction by harassment and/or gas stripping. Comparison to previous morphological studies, limited to the cluster core, suggests that galaxy-galaxy interactions may trigger the starbursts. The high e(a) galaxy fraction in Abell 851 as compared to that in the field, however, suggests that some cluster-specific mechanism, likely related to the dynamical assembly of the cluster, also contributes to the high number of starbursts.