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We present Very Large Telescope SINFONI near-infrared (NIR) integral field spectroscopy of six z ∼ 0.2 Lyman break galaxy "analogs" (LBAs) from which we detect H i, He i, and [Fe ii] recombination lines and multiple H2 rovibrational lines in emission. The Paα kinematics reveal high velocity dispersions and low rotational velocities relative to random motions (). Matched-aperture comparisons of Hβ, Hα, and Paα reveal that the nebular color excesses are lower relative to the continuum color excesses than is the case for typical local star-forming systems. We compare observed He i/H i recombination line ratios to photoionization models to gauge the effective temperatures (Teff) of massive ionizing stars, finding that the properties of at least one LBA are consistent with extra heating from an active galactic nucleus (AGN) and/or an overabundance of massive stars. We use H2 1−0 S(·) rovibrational spectra to determine a rotational excitation temperature Tex ∼ 2000 K for warm molecular gas, which we attribute to UV heating in dense photon-dominated regions. Spatially resolved NIR line ratios favor excitation by massive young stars, rather than supernova or AGN feedback. Our results suggest that the local analogs of Lyman break galaxies are primarily subject to strong feedback from recent star formation, with evidence for AGNs and outflows in some cases. [ABSTRACT FROM AUTHOR]

We present ∼1″ resolution (∼2 kpc in the source plane) observations of the CO (1–0), CO (3–2), Hα, and [N ii] lines in the strongly lensed z = 2.26 star-forming galaxy SDSS J0901+1814. We use these observations to constrain the lensing potential of a foreground group of galaxies, and our source-plane reconstructions indicate that SDSS J0901+1814 is a nearly face-on (i ≈ 30°) massive disk with r1/2 ≳ 4 kpc for its molecular gas. Using our new magnification factors (μtot ≈ 30), we find that SDSS J0901+1814 has a star formation rate (SFR) of , , and , which places it on the star-forming galaxy “main sequence.” We use our matched high angular resolution gas and SFR tracers (CO and Hα, respectively) to perform a spatially resolved (pixel-by-pixel) analysis of SDSS J0901+1814 in terms of the Schmidt–Kennicutt relation. After correcting for the large fraction of obscured star formation (), we find that SDSS J0901+1814 is offset from “normal” star-forming galaxies to higher star formation efficiencies independent of assumptions for the CO-to-H2 conversion factor. Our mean best-fit index for the Schmidt–Kennicutt relation for SDSS J0901+1814, evaluated with different CO lines and smoothing levels, is however, the index may be affected by gravitational lensing, and we find when analyzing the source-plane reconstructions. While the Schmidt–Kennicutt index largely appears unaffected by which of the two CO transitions we use to trace the molecular gas, the source-plane reconstructions and dynamical modeling suggest that the CO (1–0) emission is more spatially extended than the CO (3–2) emission. [ABSTRACT FROM AUTHOR]

We introduce the Keck OSIRIS Nearby AGN survey (KONA), a new adaptive optics-assisted integral-field spectroscopic survey of Seyfert galaxies. KONA permits at ∼0.″1 resolution a detailed study of the nuclear kinematic structure of gas and stars in a representative sample of 40 local bona fide active galactic nucleus (AGN). KONA seeks to characterize the physical processes responsible for the coevolution of supermassive black holes and galaxies, principally inflows and outflows. With these IFU data of the nuclear regions of 40 Seyfert galaxies, the KONA survey will be able to study, for the first time, a number of key topics with meaningful statistics. In this paper we study the nuclear K-band properties of nearby AGN. We find that the K-band (2.1 μm) luminosities of the compact Seyfert 1 nuclei are correlated with the hard X-ray luminosities, implying a non-stellar origin for the majority of the continuum emission. The best-fit correlation is log LK = 0.9log L2–10 keV + 4 over three orders of magnitude in both K-band and X-ray luminosities. We find no strong correlation between 2.1 μm luminosity and hard X-ray luminosity for the Seyfert 2 galaxies. The spatial extent and spectral slope of the Seyfert 2 galaxies indicate the presence of nuclear star formation and attenuating material (gas and dust), which in some cases is compact and in some galaxies extended. We detect coronal-line emission in 36 galaxies and for the first time in 5 galaxies. Finally, we find 4/20 galaxies that are usually classified as Seyfert 2 based on their optical spectra exhibit a broad component of Brγ emission, and one galaxy (NGC 7465) shows evidence of a double nucleus. [ABSTRACT FROM AUTHOR]