We analyze the spectra, spatial distributions and kinematics of Ha, NII and SII emission in a sample of 42, z~2.2 UV/optically selected star forming galaxies (SFGs) from the SINS & zC-SINF surveys, ...35 of which were observed in the adaptive optics mode of SINFONI. This is supplemented by kinematic data from 48 z~1-2.5 galaxies from the literature. We find that the kinematic classification of the high-z SFGs as `dispersion dominated' or `rotation dominated' correlates most strongly with their intrinsic sizes. Smaller galaxies are more likely `dispersion-dominated' for two main reasons: 1) The rotation velocity scales linearly with galaxy size but intrinsic velocity dispersion does not depend on size, and as such, their ratio is systematically lower for smaller galaxies, and 2) Beam smearing strongly decreases large-scale velocity gradients and increases observed dispersion much more for galaxies with sizes at or below the resolution. Dispersion dominated SFGs may thus have intrinsic properties similar to `rotation dominated' SFGs, but are primarily more compact, lower mass, less metal enriched and may have higher gas fractions, plausibly because they represent an earlier evolutionary state.
Based on SINFONI Ha, NII and SII AO data of 30 z \sim 2 star-forming galaxies (SFGs) from the SINS and zcSINF surveys, we find a strong correlation of the Ha broad flux fraction with the star ...formation surface density of the galaxy, with an apparent threshold for strong outflows occurring at 1 Msun yr^-1 kpc^-2. Above this threshold, we find that SFGs with logm_\ast>10 have similar or perhaps greater wind mass loading factors (eta = Mdotout/SFR) and faster outflow velocities than lower mass SFGs. This trend suggests that the majority of outflowing gas at z \sim 2 may derive from high-mass SFGs, and that the z \sim 2 mass-metallicity relation is driven more by dilution of enriched gas in the galaxy gas reservoir than by the efficiency of outflows. The mass loading factor is also correlated with the SFR and inclination, such that more star-forming and face-on galaxies launch more powerful outflows. For galaxies that have evidence for strong outflows, we find that the broad emission is spatially extended to at least the half-light radius (\sim a few kpc). We propose that the observed threshold for strong outflows and the observed mass loading of these winds can be explained by a simple model wherein break-out of winds is governed by pressure balance in the disk. Using the ratio of the SII doublet in a broad and narrow component, we find that outflowing gas has a density of \sim10-100 cm^-3, significantly less than that of the star forming gas (600 cm^-3).
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