Spatially Resolved Dust Maps from Balmer Decrements in Galaxies at z 1.4

Galaxie

3D-HST+CANDELS : the evolution of the galaxy size-mass distribution since z=3

Spectroscopic+photometric redshifts, stellar mass estimates, and rest-frame colors from the 3D-HST survey are combined with structural parameter measurements from CANDELS imaging to determine the galaxy size-mass distribution over the redshift range 0 < z < 3. Separating early- and late-type galaxies on the basis of star-formation activity, we confirm that early-type galaxies are on average smaller than late-type galaxies at all redshifts, and we find a significantly different rate of average size evolution at fixed galaxy mass, with fast evolution for the early-type population, R eff∝(1 + z)–1.48, and moderate evolution for the late-type population, R eff∝(1 + z)-0.75Peer reviewedFinal Accepted Versio

Erratum: “Constraining the Low-Mass Slope of the Star Formation Sequence at 0.5 < z < 2.5” (2014, ApJ, 795, 104)

This is an erratum for the article 2014 ApJ 795 10410.1088/0004-637X/795/2/104Large scale structure and cosmolog

3D-DASH: the widest near-infrared Hubble Space Telescope survey

Large scale structure and cosmolog

Diagnosing DASH: a catalog of structural properties for the COSMOS-DASH survey

Large scale structure and cosmolog

The Evolution and Origin of Ionized Gas Velocity Dispersion from z ∼ 2.6 to z ∼ 0.6 with KMOS3D

We present the 0.6<z<2.6 evolution of the ionized gas velocity dispersion in 175 star-forming disk galaxies based on data from the full KMOS3D integral field spectroscopic survey. In a forward-modeling Bayesian framework including instrumental effects and beam-smearing, we fit simultaneously the observed galaxy velocity and velocity dispersion along the kinematic major axis to derive the intrinsic velocity dispersion σ0. We find a reduction of the average intrinsic velocity dispersion of disk galaxies as a function of cosmic time, from σ0∼45 km s−1 at z∼2.3 to σ0∼30 km s−1 at z∼0.9. There is substantial intrinsic scatter (ss » 10 km s- ,int 1 0 ) around the best-fit σ0–z relation beyond what can be accounted for from the typical measurement uncertainties (δσ0≈12 km s−1), independent of other identifiable galaxy parameters. This potentially suggests a dynamic mechanism such as minor mergers or variation in accretion being responsible for the scatter. Putting our data into the broader literature context, we find that ionized and atomic+molecular velocity dispersions evolve similarly with redshift, with the ionized gas dispersion being ∼10–15 km s−1 higher on average. We investigate the physical driver of the on average elevated velocity dispersions at higher redshift and find that our galaxies are at most marginally Toomre-stable, suggesting that their turbulent velocities are powered by gravitational instabilities, while stellar feedback as a driver alone is insufficient. This picture is supported through comparison with a state-of-theart analytical model of galaxy evolution

A Consistent Study of Metallicity Evolution at 0.8 < z < 2.6

We present the correlations between stellar mass, star formation rate (SFR), and the [N II]/Hα flux ratio as an indicator of gas-phase metallicity for a sample of 222 galaxies at 0.8 < z < 2.6 and log (M */M ☉) = 9.0-11.5 from the LUCI, SINS/zC-SINF, and KMOS3D surveys. This sample provides a unique analysis of the mass-metallicity relation (MZR) over an extended redshift range using consistent data analysis techniques and a uniform strong-line metallicity indicator. We find a constant slope at the low-mass end of the relation and can fully describe its redshift evolution through the evolution of the characteristic turnover mass where the relation begins to flatten at the asymptotic metallicity. At a fixed mass and redshift, our data do not show a correlation between the [N II]/Hα ratio and SFR, which disagrees with the 0.2-0.3 dex offset in [N II]/Hα predicted by the "fundamental relation" between stellar mass, SFR, and metallicity discussed in recent literature. However, the overall evolution toward lower [N II]/Hα at earlier times does broadly agree with these predictions