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We report the detection of a massive neutral gas outflow in the z = 2.09 gravitationally lensed dusty star-forming galaxy HATLAS J085358.9+015537 (G09v1.40), seen in absorption with the OH+(11−10) transition using spatially resolved (0.″5 × 0.″4) Atacama Large Millimeter/submillimeter Array (ALMA) observations. The blueshifted OH+ line is observed simultaneously with the CO(9−8) emission line and underlying dust continuum. These data are complemented by high-angular-resolution (0.″17 × 0.″13) ALMA observations of CH+(1−0) and underlying dust continuum, and Keck 2.2 μm imaging tracing the stellar emission. The neutral outflow, dust, dense molecular gas, and stars all show spatial offsets from each other. The total atomic gas mass of the observed outflow is 6.7 × 109M⊙, >25% as massive as the gas mass of the galaxy. We find that a conical outflow geometry best describes the OH+ kinematics and morphology and derive deprojected outflow properties as functions of possible inclination (0.°38–64°). The neutral gas mass outflow rate is between 83 and 25,400 M⊙ yr−1, exceeding the star formation rate (788 ± 300 M⊙ yr−1) if the inclination is >3.°6 (mass-loading factor = 0.3–4.7). Kinetic energy and momentum fluxes span (4.4–290) × 109L⊙ and (0.1–3.7) × 1037 dyne, respectively (energy-loading factor = 0.013–16), indicating that the feedback mechanisms required to drive the outflow depend on the inclination assumed. We derive a gas depletion time between 29 and 1 Myr, but find that the neutral outflow is likely to remain bound to the galaxy unless the inclination is small and may be reaccreted if additional feedback processes do not occur. [ABSTRACT FROM AUTHOR]

We report new observations toward the hyperluminous dusty starbursting major merger ADFS-27 (z = 5.655), using the Australia Telescope Compact Array (ATCA) and the Atacama Large Millimeter/submillimeter Array (ALMA). We detect CO (J = 2 → 1), CO (J = 8 → 7), CO (J = 9 → 8), CO (J = 10 → 9), and H2O (312 → 221) emission, and a P Cygni−shaped OH+ (11 → 01) absorption/emission feature. We also tentatively detect H2O (321 → 312) and OH+ (12 → 01) emission and CH+ (J = 1 → 0) absorption. We find a total cold molecular mass of Mgas = (2.1 ± 0.2) × 1011 (αCO/1.0) M⊙. We also find that the excitation of the star-forming gas is overall moderate for a z > 5 dusty starburst, which is consistent with its moderate dust temperature. A high-density, high kinetic temperature gas component embedded in the gas reservoir is required to fully explain the CO line ladder. This component is likely associated with the "maximum starburst" nuclei in the two merging galaxies, which are separated by only 140 ± 13 km s−1 along the line of sight and 9.0 kpc in projection. The kinematic structure of both components is consistent with galaxy disks, but this interpretation remains limited by the spatial resolution of the current data. The OH+ features are only detected toward the northern component, which is also the one that is more enshrouded in dust and thus remains undetected up to 1.6 μm even in our sensitive new Hubble Space Telescope Wide Field Camera 3 imaging. The absorption component of the OH+ line is blueshifted and peaks near the CO and continuum emission peak, while the emission is redshifted and peaks offset by 1.7 kpc from the CO and continuum emission peak, suggesting that the gas is associated with a massive molecular outflow from the intensely star-forming nucleus that supplies 125 M⊙ yr−1 of enriched gas to its halo. [ABSTRACT FROM AUTHOR]

We present an Atacama Large Millimeter/submillimeter Array observation of the Submillimeter galaxy ID 141 at z = 4.24 in the [N ii ] 205 μm line (hereafter [N ii ]) and the underlying continuum at (rest-frame) 197.6 μm. Benefiting from lensing magnification by a galaxy pair at z = 0.595, ID 141 is one of the brightest SMGs. At the angular resolutions of –1.″5 (1″ ∼6.9 kpc), our observation clearly separates and moderately resolves the two lensed images in both continuum and line emission at a signal-to-noise ratio >5. Our continuum-based lensing model implies an averaged amplification factor of ∼5.8 and reveals that the delensed continuum image has a Sérsic index and Sérsic radius of ∼0.″18 (∼1.24 kpc). Furthermore, the reconstructed [N ii ] velocity field in the source plane is dominated by a rotation component with a maximum velocity of ∼300 km s−1 at large radii, indicating a dark matter halo mass of ∼10. This, together with the reconstructed velocity dispersion field being smooth and modest in value (<100 km s−1) over much of the outer parts of the galaxy, favors the interpretation of ID 141 being a disk galaxy dynamically supported by rotation. The observed [N ii ] /CO (7−6) and [N ii ] /[C ii ] 158 μm line-luminosity ratios, which are consistent with the corresponding line ratio versus far-infrared color correlation from local luminous infrared galaxies, imply a delensed star formation rate of (1.8 yr−1 and provide an independent estimate of the size of the star-forming region kpc in radius. [ABSTRACT FROM AUTHOR]

Local luminous infrared (IR) galaxies (LIRGs) have both high star formation rates (SFR) and a high AGN (Seyfert and AGN/starburst composite) incidence. Therefore, they are ideal candidates to explore the co-evolution of black hole (BH) growth and star formation (SF) activity, not necessarily associated with major mergers. Here, we use Spitzer/IRS spectroscopy of a complete volume-limited sample of local LIRGs (distances of<78 Mpc).We estimate typical BH masses of 3 × 107M☉ using [Ne III] 15.56μm and optical [O III] λ5007 gas velocity dispersions and literature stellar velocity dispersions.We find that in a large fraction of local LIRGs, the current SFR is taking place not only in the inner nuclear ∼1.5 kpc region, as estimated from the nuclear 11.3μm PAH luminosities, but also in the host galaxy. We next use the ratios between the SFRs and BH accretion rates (BHAR) to study whether the SF activity and BH growth are contemporaneous in local LIRGs. On average, local LIRGs have SFR to BHAR ratios higher than those of optically selected Seyferts of similar active galactic nucleus (AGN) luminosities. However, the majority of the IR-bright galaxies in the revised-Shapley-Ames Seyfert sample behave like local LIRGs. Moreover, the AGN incidence tends to be higher in local LIRGs with the lowest SFRs. All of this suggests that in local LIRGs there is a distinct IR-bright star-forming phase taking place prior to the bulk of the current BH growth (i.e., AGN phase). The latter is reflected first as a composite and then as a Seyfert, and later as a non-LIRG optically identified Seyfert nucleus with moderate SF in its host galaxy. [ABSTRACT FROM AUTHOR]

We quantify the active galactic nucleus (AGN) contribution to the mid-infrared (mid-IR) and the total infrared (IR, 8-1000 µm) emission in a complete volume-limited sample of 53 local luminous infrared galaxies (LIRGs, LIR = 1011-1012 L⊙). We decompose the Spitzer Infrared Spectrograph low-resolution 5-38 µm spectra of the LIRGs into AGN and starburst components using clumpy torus models and star-forming galaxy templates, respectively. We find that 50% (25/50) of local LIRGs have an AGN component detected with this method. There is good agreement between these AGN detections through mid-IR spectral decomposition and other AGN indicators, such as the optical spectral class, mid-IR spectral features, and X-ray properties. Taking all the AGN indicators together, the AGN detection rate in the individual nuclei of LIRGs is ~62%. The derived AGN bolometric luminosities are in the range Lbol(AGN) = (0.4-50) x 1043 erg s-1. The AGN bolometric contribution to the IR luminosities of the galaxies is generally small, with 70% of LIRGs having Lbol[AGN]/LIR ≤, 0.05. Only ≃ 8% of local LIRGs have a significant AGN bolometric contribution Lbol[AGN]/LIR > 0.25. From the comparison of our results with literature results of ultraluminous infrared galaxies (LIR = 1012-1013 L⊙), we confirm that in the local universe the AGN bolometric contribution to the IR luminosity increases with the IR luminosity of the galaxy/system. If we add up the AGN bolometric luminosities we find that AGNs only account for Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed of the total IR luminosity produced by local LIRGs (with and without AGN detections). This proves that the bulk of the IR luminosity of local LIRGs is due to star formation activity. Taking the newly determined IR luminosity density of LIRGs in the local universe, we then estimate an AGN IR luminosity density of Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed in LIRGs. [ABSTRACT FROM AUTHOR]

We report Herschel SPIRE (250, 350, and 500 μm) detections of 32 quasars with redshifts 0.5 ⩽z < 3.6 from the Herschel Multi-tiered Extragalactic Survey (HerMES). These sources are from a MIPS 24 μm flux-limited sample of 326 quasars in the Lockman Hole Field. The extensive multi-wavelength data available in the field permit construction of the rest-frame spectral energy distributions (SEDs) from ultraviolet to the mid-infrared for all sources, and to the far-infrared (FIR) for the 32 objects. Most quasars with Herschel FIR detections show dust temperatures in the range of 25-60 K, with a mean of 34 K. The FIR luminosities range from 1011.3 to 1013.5L☼, qualifying most of their hosts as ultra- or hyper-luminous infrared galaxies. These FIR-detected quasars may represent a dust-rich population, but with lower redshifts and fainter luminosities than quasars observed at ∼1 mm. However, their FIR properties cannot be predicted from shorter wavelengths (0.3-20 μm, rest frame), and the bolometric luminosities derived using the 5100 Å index may be underestimated for these FIR-detected quasars. Regardless of redshift, we observed a decline in the relative strength of FIR luminosities for quasars with higher near-infrared luminosities. [ABSTRACT FROM AUTHOR]