We present the KMOS 3D survey, a new integral field survey of over 600 galaxies at 0.7 < z < 2.7 using KMOS at the Very Large Telescope. The KMOS 3D survey utilizes synergies with multi-wavelength ground-and spacebased surveys to trace the evolution of spatially resolved kinematics and star formation from a homogeneous sample over 5 Gyr of cosmic history. Targets, drawn from a mass-selected parent sample from the 3D-HST survey, cover the star formation-stellar mass (M * ) and rest-frame (U − V ) − M * planes uniformly. We describe the selection of targets, the observations, and the data reduction. In the first-year of data we detect Hα emission in 191 M * = 3 × 10 9 -7 × 10 11 M galaxies at z = 0.7-1.1 and z = 1.9-2.7. In the current sample 83% of the resolved galaxies are rotation dominated, determined from a continuous velocity gradient and v rot /σ 0 > 1, implying that the star-forming "main sequence" is primarily composed of rotating galaxies at both redshift regimes. When considering additional stricter criteria, the Hα kinematic maps indicate that at least ∼70% of the resolved galaxies are disk-like systems. Our high-quality KMOS data confirm the elevated velocity dispersions reported in previous integral field spectroscopy studies at z 0.7. For rotation-dominated disks, the average intrinsic velocity dispersion decreases by a factor of two from 50 km s −1 at z ∼ 2.3 to 25 km s −1 at z ∼ 0.9. Combined with existing results spanning z ∼ 0-3, we show that disk velocity dispersions follow an evolution that is consistent with the dependence of velocity dispersion on gas fractions predicted by marginally stable disk theory.

Based on a uniform dynamical analysis of the line-profile shapes of 21 mostly luminous, slowly rotating, and nearly round elliptical galaxies, we have investigated the dynamical family relations and dark halo properties of ellipticals. Our results include: (i) The circular velocity curves (CVCs) of elliptical galaxies are flat to within ≃ 10% for R ∼ > 0.2R e . (ii) Most ellipticals are moderately radially anisotropic; their dynamical structure is surprisingly uniform. (iii) Elliptical galaxies follow a Tully-Fisher (TF) relation with marginally shallower slope than spiral galaxies, and v max c ≃ 300 km s −1 for an L * B galaxy. At given circular velocity, they are ∼ 1 mag fainter in B and ∼ 0.6 mag in R, and appear to have slightly lower baryonic mass than spirals, even for the maximum M/L B allowed by the kinematics. (iv) The luminosity dependence of M/L B indicated by the tilt of the Fundamental Plane (FP) is confirmed. The tilt of the FP is not caused by dynamical or photometric non-homology, although the latter might influence the slope of M/L versus L. It can also not be due only to an increasing dark matter fraction with L for the range of IMF currently discussed. It is, however, consistent with stellar population models based on published metallicities and ages. The main driver is therefore probably metallicity, and a secondary population effect is needed to explain the K-band tilt. (v) These results make it likely that elliptical galaxies have nearly maximal M/L B (minimal halos). (vi) Despite the uniformly flat CVCs, there is a spread in the luminous to dark matter ratio and in cumulative M/L B (r). Some galaxies have no indication for dark matter within 2R e , whereas for others we obtain local M/L B s of 20-30 at 2R e . (vii) In models with maximum stellar mass, the dark matter contributes ∼ 10 − 40% of the mass within R e . Equal interior mass of dark and luminous matter is predicted at ∼ 2−4R e . (viii) Even in these maximum stellar mass models, the halo core densities and phase-space densities are at least ∼ 25 times larger and the halo core radii ∼ 4 times smaller than in spiral galaxies of the same circular velocity. The increase in M/L sets in at ∼ 10 times larger acceleration than in spirals. This could imply that elliptical galaxy halos collapsed at high redshift or that some of the dark matter in ellipticals might be baryonic.The dynamical structure of these galaxies turned out to be remarkably uniform. Most galaxies require moderate radial anisotropy in their main bodies (at ∼ 0.5R e ). Their circular velocity curves are all consistent with being flat outside ≃ 0.2R e . The M/L ratio profiles begin to rise at around 0.5 − 2R e and are consistent with X-ray and other data where available, although from the kinematic data alone constant M/L models can only be ruled out at 95% confidence in a few galaxies.This sample provides a new and much improved basis for investigating the dynamical family properties of elliptical galaxies, which is the subject of the present study. In Section 2, we analyze...

28 pages, 19 figures, ApJ in pressInternational audienceWe study how the proportion of star-forming galaxies evolves between z=0.8 and 0 as a function of galaxy environment, using the O II line in emission as a signature of ongoing star formation. Our high-z data set comprises 16 clusters, 10 groups, and another 250 galaxies in poorer groups and the field at z=0.4-0.8 from the ESO Distant Cluster Survey, plus another 9 massive clusters at similar redshifts. As a local comparison, we use galaxy systems selected from the Sloan Digital Sky Survey (SDSS) at 0.04=550 km s-1, where the fraction of galaxies with O II emission does not vary systematically with velocity dispersion. We quantify the evolution of the proportion of star-forming galaxies as a function of the system velocity dispersion and find that it is strongest in intermediate-mass systems (?~500-600 km s-1 at z=0). To understand the origin of the observed trends, we use the Press-Schechter formalism and the Millennium Simulation and show that galaxy star formation histories may be closely related to the growth history of clusters and groups. If the scenario we propose is roughly correct, the link between galaxy properties and environment is extremely simple to predict purely from a knowledge of the growth of dark matter structures. Based on observations obtained at the ESO Very Large Telescope (VLT) as part of the Large program 166.A-0162 (the ESO Distant Cluster Survey). Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with proposal 9476