We have obtained high spatial resolution Keck OSIRIS integral field spectroscopy of four z~1.5 ultra-luminous infrared galaxies that exhibit broad H-alpha emission lines indicative of strong AGN activity. The observations were made with the Keck laser guide star adaptive optics system giving a spatial resolution of 0.1", or <1 kpc at these redshifts. These high spatial resolution observations help to spatially separate the extended narrow-line regions --- possibly powered by star formation --- from the nuclear regions, which may be powered by both star formation and AGN activity. There is no evidence for extended, rotating gas disks in these four galaxies. Assuming dust correction factors as high as A(H-alpha)=4.8 mag, the observations suggest lower limits on the black hole masses of (1 - 9) x 10^8 solar masses, and star formation rates <100 solar masses per year. The black hole masses and star formation rates of the sample galaxies appear low in comparison to other high-z galaxies with similar host luminosities. We explore possible explanations for these observations including, host galaxy fading, black hole growth, and the shut down of star formation.
We present H- and K-band data from the inner arcsecond of the Seyfert 1.5 galaxy NGC 4151 obtained with the adaptive optics assisted near-infrared imaging field spectrograph OSIRIS at the Keck Observatory. We present the morphology and dynamics of most species detected but focus on the morphology and dynamics of the narrow line region (as traced by emission of [FeII] λ1.644μm), the interplay between plasma ejected from the nucleus (as traced by 21 cm continuum radio data) and hot H2 gas and characterize the detected nuclear HeI$λ2.058 μm absorption feature as a narrow absorption line (NAL) phe…
A simple optical to mid-IR color selection, R-[24] > 14, i.e. f_nu(24) / f_nu(R) > 1000, identifies highly dust obscured galaxies (DOGs) with typical redshifts of z~2 +/- 0.5. Extreme mid-IR luminosities (L_{IR} > 10^{12-14}) suggest that DOGs are powered by a combination of AGN and star formation, possibly driven by mergers. In an effort to compare their photometric properties with their rest frame optical morphologies, we obtained high spatial resolution (0.05 -0.1") Keck Adaptive Optics (AO) K'-band images of 15 DOGs. The images reveal a wide range of morphologies, including: small exponent…
We present the first Keck/OSIRIS infrared IFU observations of a high redshift damped Lyman-alpha (DLA) galaxy detected in the line of sight to a background quasar. By utilizing the Laser Guide Star Adaptive Optics (LGSAO) to reduce the quasar PSF to FWHM~0.15 arcsec, we were able to search for and map the foreground DLA emission free from the quasar contamination. We present maps of the H-alpha and [OIII] $λλ$ 5007, 4959 emission of DLA 2222-0946 at a redshift of z ~ 2.35. From the composite spectrum over the H-alpha emission region we measure a star formation rate of 9.5 $\pm$ 1.0 M$_{\odot}$…
We present a 3-dimensional data cube of the K band continuum and the Br-gamma, H2 S(0) and S(1) lines within the central 18.5" x 13.8" (520 pc x 390 pc) region of NGC 6946. Data were obtained using OSIRIS, a near-infrared Integral Field Unit at Keck Observatory, with Laser Guide Star Adaptive Optics. The 0.3" resolution allows us to investigate the stellar bulge and the forming star clusters in the nuclear region on 10 parsec scales. We detect giant HII regions associated with massive young star clusters in the nuclear spiral/ring (R ~ 30pc) and in the principal shocks along the nuclear bar. C…
We have observed Halpha emission from a sample of 13 star-forming galaxies from the WiggleZ Dark Energy Survey in the redshift range z~1.2-1.5 and stellar mass range 9.8<log(M_*/M_sun)<11.6 with the integral field spectrograph OSIRIS on Keck, taking advantage of Laser Guide Star Adaptive Optics. We detect multiple emission, 1-2 kpc size sub-components, or 'clumps' within the Halpha spatial emission in 4 galaxies, extended emission in 4 galaxies and compact spheroidal emission in 5 galaxies. Considering our results in the context of unstable disk formation and a merger sequence, we find evidenc…
We present Keck laser guide star adaptive optics observations of the nearby buried QSO F08572+3915:NW. We use near-infrared integral field data taken with OSIRIS to reveal a compact disk and molecular outflow using Pa-alpha and H_2 rotational-vibrational transitions at a spatial resolution of 100 pc. The outflow emerges perpendicular to the disk into a bicone of one-sided opening angle 100 degrees up to distances of 400 pc from the nucleus. The integrated outflow velocities, which reach at least -1300 km/s, correspond exactly to those observed in (unresolved) OH absorption, but are smaller (la…
We present near-infrared imaging spectroscopy of the strongly-lensed z=2.00 galaxy SDSS J120601.69+514227.8 (`the Clone arc'). Using OSIRIS on the Keck 2 telescope with laser guide star adaptive optics, we achieve resolved spectroscopy with 0.20 arcsecond FWHM resolution in the diagnostic emission lines [O III], Halpha, and [N II]. The lensing magnification allows us to map the velocity and star formation from Halpha emission at a physical resolution of ~300 pc in the galaxy source plane. With an integrated star formation rate of ~50 Msun/yr, the galaxy is typical of sources similarly studied …
Hot, Dust-Obscured Galaxies (Hot DOGs), selected from the WISE all sky infrared survey, host some of the most powerful Active Galactic Nuclei (AGN) known, and might represent an important stage in the evolution of galaxies. Most known Hot DOGs are at $z> 1.5$, due in part to a strong bias against identifying them at lower redshift related to the selection criteria. We present a new selection method that identifies 153 Hot DOG candidates at $z\sim 1$, where they are significantly brighter and easier to study. We validate this approach by measuring a redshift $z=1.009$, and an SED similar to hig…
High-resolution observations in the near infrared show star clusters around the active galactic nucleus (AGN) of the Seyfert 1 NGC2110, along with a 90 x 35 pc bar of shocked gas material around its nucleus. These are seen for the first time in our imaging and gas kinematics of the central 100pc with the Keck OSIRIS instrument with adaptive optics. Each of these clusters is 2-3 times brighter than the Arches cluster close to the centre of the Milky Way. The core star formation rate (SFR) is 0.3 M$_\odot$/yr. The photoionized gas (He I) dynamics imply an enclosed mass of 3-4 x 10$^8$ M$_\odot$.…
We present a detailed analysis of multi-wavelength HST/WFC3 imaging and Keck/OSIRIS near-IR AO-assisted integral field spectroscopy for a highly magnified lensed galaxy at z=1.70. This young starburst is representative of UV-selected star-forming galaxies (SFG) at z~2 and contains multiple individual star-forming regions. Due to the lensing magnification, we can resolve spatial scales down to 100pc in the source plane of the galaxy. The velocity field shows disturbed kinematics suggestive of an ongoing interaction, and there is a clear signature of a tidal tail. We constrain the age, reddening…
We present results for 19 "Lyman Break Analogs" (LBAs) observed with Keck/OSIRIS with an AO-assisted spatial resolution of less than 200 pc. We detect satellites/companions, diffuse emission and velocity shear, all with high signal-to-noise ratios. These galaxies present remarkably high velocity dispersion along the line of sight(- 70 km s-1), much higher than standard star-forming spirals in the low-redshift universe. We artificially redshift our data to z - 2.2 to allow for a direct comparison with observations of high-z LBGs and find striking similarities between both samples. This suggests…
(Abridged) To investigate the black hole mass (MBH) vs. stellar velocity dispersion relation of active galaxies, we measured the velocity dispersions of a sample of local Seyfert 1 galaxies, for which we have recently determined MBH using reverberation mapping. For most objects, velocity dispersions were measured from high S/N ratio optical spectra centered on the Ca II triplet region (~8500 A), obtained at the Keck, Palomar, and Lick Observatories. For two objects, in which the Ca II triplet region was contaminated by nuclear emission, the measurement was based on high-quality H-band spectra …
Lyman Break Analogs (LBAs), characterized by high far-UV luminosities and surface brightnesses as detected by GALEX, are intensely star-forming galaxies in the low-redshift universe ($z\sim 0.2$), with star formation rates reaching up to 50 times that of the Milky Way. These objects present metallicities, morphologies and other physical properties similar to higher redshift Lyman Break Galaxies (LBGs), motivating the detailed study of LBAs as local laboratories of this high-redshift galaxy population. We present results from our recent integral-field spectroscopy survey of LBAs with Keck/OSIRI…
We report a new technique to select 1.6<z<4.6 dusty Lyman-alpha emitters (LAEs), over a third of which are `blobs' (LABs) with emission extended on scales of 30-100kpc. Combining data from the NASA Wide-field Infrared Survey Explorer (WISE) mission with optical spectroscopy from the W.M. Keck telescope, we present a color criteria that yields a 78% success rate in identifying rare, dusty LAEs of which at least 37% are LABs. The objects have a surface density of only ~0.1 per square degree, making them rare enough that they have been largely missed in narrow surveys. We measured spectroscopic r…
We present the first integral-field spectroscopic observations of high-redshift submillimeter-selected galaxies (SMGs) using Laser Guide Star Adaptive Optics (LGS-AO). We target H-alpha emission of three SMGs at redshifts z~1.4-2.4 with the OH-Suppressing Infrared Imaging Spectrograph (OSIRIS) on Keck. The spatially-resolved spectroscopy of these galaxies reveals unresolved broad H-alpha line regions (FWHM>1000 km/s) likely associated with an AGN and regions of diffuse star formation traced by narrow-line H-alpha emission (FWHM<500 km/s) dominated by multiple Halpha-bright stellar clumps, each…
We present the results of a spectroscopic survey of the kinematic structure of star-forming galaxies at redshift z ~ 2 - 3 using Keck/OSIRIS integral field spectroscopy. Our sample is comprised of 12 galaxies between redshifts z ~ 2.0 and 2.5 and one galaxy at z ~ 3.3 which are well detected in either HAlpha or [O III] emission. These observations were obtained in conjunction with the Keck laser guide star adaptive optics system, with a typical angular resolution after spatial smoothing ~ 0.15" (approximately 1 kpc at the redshift of the target sample). At most five of these 13 galaxies have s…
Most massive galaxies contain supermassive black holes (SMBHs) in their cores. When galaxies merge, gas is driven to nuclear regions and can accrete onto the central black hole. Thus one expects to see dual AGN in a fraction of galaxy mergers. Candidates for galaxies containing dual AGN have been identified by the presence of double-peaked narrow [O III] emission lines and by high spatial resolution images of close galaxy pairs. Spatially-resolved spectroscopy is needed to confirm these galaxy pairs as systems with spatially-separated double SMBHs. With the Keck 2 Laser Guide Star Adaptive Opt…
We present spatially-resolved dynamics for six strongly lensed star-forming galaxies at z=1.7-3.1, each enlarged by a linear magnification factor ~8. Using the Keck laser guide star AO system and the OSIRIS integral field unit spectrograph we resolve kinematic and morphological detail in our sample with an unprecedented fidelity, in some cases achieving spatial resolutions of ~100 pc. With one exception our sources have diameters ranging from 1-7 kpc, star formation rates of 2-40 Msun/yr (uncorrected for extinction) and dynamical masses of 10^(9.7-10.3) Msun. With this exquisite resolution we …
We report evidence of ordered orbital motion in luminous star-forming galaxies at z~1.3. We present integral field spectroscopy (IFS) observations, performed with the OH Suppressing InfraRed Imaging Spectrograph (OSIRIS) system, assisted by laser guide star adaptive optics on the Keck telescope, of 13 star-forming galaxies selected from the WiggleZ Dark Energy Survey. Selected via ultraviolet and [OII] emission, the large volume of the WiggleZ survey allows the selection of sources which have comparable intrinsic luminosity and stellar mass to IFS samples at z>2. Multiple 1-2 kpc size sub-comp…
We present the first direct measurement of the central black hole mass, M_BH, in NGC 6086, the Brightest Cluster Galaxy (BCG) in Abell 2162. Our investigation demonstrates for the first time that stellar dynamical measurements of M_BH in BCGs are possible beyond the nearest few galaxy clusters. We observed NGC 6086 with laser guide star adaptive optics and the integral-field spectrograph (IFS) OSIRIS at the W.M. Keck Observatory, and with the seeing-limited IFS GMOS-N at Gemini Observatory North. We combined the two IFS data sets with existing major-axis kinematics, and used axisymmetric stell…
We present [OIII 5007A] observations of the star forming galaxy HDF-BMZ1299 (z=1.598) using Keck Observatory's Adaptive Optics system with the near-infrared integral field spectrograph OSIRIS. Using previous Halpha and [NII] measurements of the same source, we are able for the first time to use spatially resolved observations to place a high-redshift galaxy's substructure on a traditional HII diagnostic diagram. We find that HDF-BMZ1299's spatially concentrated nebular ratios in the central ~1.5 kiloparsec (0."2) are best explained by the presence of an AGN: log([NII]/Halpha)=-0.22+/-0.05 and …
Strong gravitational lenses can be used to detect low mass subhalos, based on deviations in image fluxes and positions from what can be achieved with a smooth mass distribution. So far, this method has been limited by the small number of (radio-loud, microlensing free) systems which can be analysed for the presence of substructure. Using the gravitational lens B1422+231, we demonstrate that adaptive optics integral field spectroscopy can also be used to detect dark substructures. We analyse data obtained with OSIRIS on the Keck I Telescope, using a Bayesian method that accounts for uncertainti…
