We present high angular resolution multiwavelength data of the 3C 298 radio-loud quasar host galaxy (z = 1.439) taken using the W.M. Keck Observatory OSIRIS integral field spectrograph (IFS) with adaptive optics, the Atacama Large Millimeter/submillimeter Array (ALMA), the Hubble Space Telescope (HST) WFC3, and the Very Large Array (VLA). Extended emission is detected in the rest-frame optical nebular emission lines Hβ, [O III], Hα, [N II], and [S II], as well as in the molecular lines CO (J = 3−2) and (J = 5−4). Along the path of the relativistic jets of 3C 298, we detect conical outflows in ionized gas emission with velocities of up to 1700 km s 1 -and an outflow rate of 450-1500 M yr 1 - extended over 12 kpc. Near the spatial center of the conical outflow, CO (J = 3−2) emission shows a molecular gas disk with a rotational velocity of±150 km s 1 -and total molecular mass (M H 2 ) of M 6.6 0.36 10 9 ´. On the blueshifted side of the molecular disk, we observe broad extended emission that is due to a molecular outflow with a rate of 2300 M yr 1 - and depletion timescale of 3 Myr. We detect no narrow Hαemission in the outflow regions, suggesting a limit on star formation of 0.3 M yr kpc. Quasardriven winds are evacuating the molecular gas reservoir, thereby directly impacting star formation in the host galaxy. The observed mass of the supermassive black hole is M 10 9.37 9.56  -,and we determine a dynamical bulge mass of M M 1 1.7 10 R bulge 10 1.6 kpc =´ -. The bulge mass of 3C 298 lies 2-2.5 orders of magnitude below the expected value from the local galactic bulge-supermassive black hole mass (M M bulge BH -) relationship. A second galactic disk observed in nebular emission is offset from the quasar by 9 kpc, suggesting that the system is an intermediate-stage merger. These results show that galactic-scale negative feedback is occurring early in the merger phase of 3C 298, well before the coalescence of the galactic nuclei and assembly on the local M M bulge BH -relationship.

We present results from IROCKS (Intermediate Redshift OSIRIS Chemo-Kinematic Survey) for sixteen z ∼ 1 and one z ∼ 1.4 star-forming galaxies. All galaxies were observed with OSIRIS with the laser guide star adaptive optics system at Keck Observatory. We use rest-frame nebular Hα emission lines to trace morphologies and kinematics of ionized gas in star-forming galaxies on sub-kiloparsec physical scales. We observe elevated velocity dispersions (σ 50 km s −1 ) seen in z > 1.5 galaxies persist at z ∼ 1 in the integrated galaxies. Using an inclined disk model and the ratio of v/σ, we find that 1/3 of the z ∼ 1 sample are disk candidates while the other 2/3 of the sample are dominated by merger-like and irregular sources. We find that including extra attenuation towards HII regions derived from stellar population synthesis modeling brings star formation rates (SFR) using Hα and stellar population fit into a better agreement. We explore properties of compact Hα sub-component, or "clump," at z ∼ 1 and find that they follow a similar size-luminosity relation as local HII regions but are scaled-up by an order of magnitude with higher luminosities and sizes. Comparing the z ∼ 1 clumps to other high-redshift clump studies, we determine that the clump SFR surface density evolves as a function of redshift. This may imply clump formation is directly related to the gas fraction in these systems and support disk fragmentation as their formation mechanism since gas fraction scales with redshift.

We present black hole mass measurements from kinematic modeling of high-spatial resolution integral field spectroscopy of the inner regions of nine nearby (ultra-)luminous infrared galaxies in a variety of merger stages. These observations were taken with OSIRIS and laser guide star adaptive optics on the Keck I and Keck II telescopes, and reveal gas and stellar kinematics inside the spheres of influence of these supermassive black holes. We find that this sample of black holes are overmassive (∼10 7-9 ☉ M ) compared to the expected values based on black hole scaling relations, and suggest that the major epoch of black hole growth occurs in early stages of a merger, as opposed to during a final episode of quasar-mode feedback. The black hole masses presented are the dynamical masses enclosed in ∼25 pc, and could include gas which is gravitationally bound to the black hole but has not yet lost sufficient angular momentum to be accreted. If present, this gas could in principle eventually fuel active galactic nucleus feedback or be itself blown out from the system.

OSIRIS is a near-infrared integral field spectrograph operating behind the adaptive optics system at W. M. Keck Observatory. While OSIRIS has been a scientifically productive instrument to date, its sensitivity has been limited by a grating efficiency that is less than half of what was expected. The spatially averaged efficiency of the old grating, weighted by error, is measured to be 39.5 ± 0.8 % at λ = 1.310 µm, with large field dependent variation of 11.7 % due to efficiency variation across the grating surface. Working with a new vendor, we developed a more efficient and uniform grating with a weighted average efficiency at λ = 1.310 µm of 78.0 ± 1.6 %, with field variation of only 2.2 %. This is close to double the average efficiency and five times less variation across the field. The new grating was installed in December 2012, and onsky OSIRIS throughput shows an average factor of 1.83 improvement in sensitivity between 1 and 2.4 microns. We present the development history, testing, and implementation of this new near-infrared grating for OSIRIS and report the comparison with the predecessors. The higher sensitivities are already having a large impact on scientific studies with OSIRIS.