scholarly journals The gentle monster PDS 456

2019 ◽  
Vol 628 ◽  
pp. A118 ◽  
Author(s):  
M. Bischetti ◽  
E. Piconcelli ◽  
C. Feruglio ◽  
F. Fiore ◽  
S. Carniani ◽  
...  

We report on the first ALMA observation of the CO(3−2) and rest-frame ∼340 GHz continuum emission in PDS 456, which is the most luminous, radio-quiet QSO in the local Universe (z ≃ 0.18), with a bolometric luminosity LBol ∼ 1047 erg s−1. ALMA angular resolution allowed us to map scales as small as ∼700 pc. The molecular gas reservoir traced by the core of the very bright CO(3−2) emission line is distributed in a compact rotating disk, with a size of ∼1.3 kpc, seen close to face-on (i ∼ 25 deg). Fast CO(3−2) emission in the velocity range v ∈ [ − 1000, 500] km s−1 is also present. Specifically, we detect several blue-shifted clumps out to ∼5 kpc from the nucleus, in addition to a compact (R ≲ 1.2 kpc), broad emission component. These components reveal a galaxy-wide molecular outflow, with a total mass Mmolout ∼ 2.5 × 108 M⊙ (for an αCO = 0.8 M⊙ (K km s−1 pc2)−1) and a mass outflow rate Ṁmol ∼ 290 M⊙ yr−1. The corresponding depletion time is τdep ∼ 8 Myr, shorter than the rate at which the molecular gas is converted into stars, indicating that the detected outflow is potentially able to quench star-formation in the host. The momentum flux of the molecular outflow normalised to the radiative momentum output (i.e. LBol/c) is ≲1, comparable to that of the X-ray ultra-fast outflow (UFO) detected in PDS 456. This is at odds with the expectations for an energy-conserving expansion suggested for most of the large-scale outflows detected in low-luminosity AGNs so far. We suggest three possible scenarios that may explain this observation: (i) in very luminous AGNs such as our target the molecular gas phase is tracing only a fraction of the total outflowing mass; (ii) a small coupling between the shocked gas by the UFO and the host-galaxy interstellar medium (ISM); and (iii) AGN radiation pressure may be playing an important role in driving the outflow.

2019 ◽  
Vol 628 ◽  
pp. A65 ◽  
Author(s):  
A. Alonso-Herrero ◽  
S. García-Burillo ◽  
M. Pereira-Santaella ◽  
R. I. Davies ◽  
F. Combes ◽  
...  

ALMA observations have revealed nuclear dusty molecular disks or tori with characteristic sizes 15−40 pc in the few Seyferts and low -luminosity AGN that have been studied so far. These structures are generally decoupled both morphologically and kinematically from the host galaxy disk. We present ALMA observations of the CO(2–1) and CO(3–2) molecular gas transitions and associated (sub-) millimeter continua of the nearby Seyfert 1.5 galaxy NGC 3227 with angular resolutions 0.085 − 0.21″ (7–15 pc). On large scales, the cold molecular gas shows circular motions as well as streaming motions on scales of a few hundred parsecs that are associated with a large-scale bar. We fit the nuclear ALMA 1.3 mm emission with an unresolved component and an extended component. The 850 μm emission shows at least two extended components, one along the major axis of the nuclear disk, and the other along the axis of the ionization cone. The molecular gas in the central region (1″ ∼ 73 pc) shows several CO clumps with complex kinematics that appears to be dominated by noncircular motions. While we cannot conclusively demonstrate the presence of a warped nuclear disk, we also detected noncircular motions along the kinematic minor axis. They reach line-of-sight velocities of v − vsys = 150 − 200 km s−1. Assuming that the radial motions are in the plane of the galaxy, we interpret them as a nuclear molecular outflow due to molecular gas in the host galaxy that is entrained by the AGN wind. We derive molecular outflow rates of 5 M⊙ yr−1 and 0.6 M⊙ yr−1 at projected distances of up to 30 pc to the northeast and southwest of the AGN, respectively. At the AGN location we estimate a mass in molecular gas of 5 × 105 M⊙ and an equivalent average column density N(H2) = 2 − 3 × 1023 cm−2 in the inner 15 pc. The nuclear CO(2–1) and CO(3–2) molecular gas and submillimeter continuum emission of NGC 3227 do not resemble the classical compact torus. Rather, these emissions extend for several tens of parsecs and appear connected with the circumnuclear ring in the host galaxy disk, as found in other local AGN.


2019 ◽  
Vol 632 ◽  
pp. A66 ◽  
Author(s):  
Tom Oosterloo ◽  
Raffaella Morganti ◽  
Clive Tadhunter ◽  
J. B. Raymond Oonk ◽  
Hayley E. Bignall ◽  
...  

We present CO(1−0) and CO(3−2) Atacama Large Millimeter/submillimeter Array observations of the molecular gas in PKS 1549−79, as well as mm and very long baseline interferometry 2.3-GHz continuum observations of its radio jet. PKS 1549−79 is one of the closest young, radio-loud quasars caught in an on-going merger in which the active galactic nucleus (AGN) is in the first phases of its evolution. We detect three structures tracing the accretion and the outflow of molecular gas: kpc-scale tails of gas accreting onto PKS 1549−79 from a merger, a circumnuclear disc in the inner few hundred parsec, and a very broad (> 2300 km s−1) component detected in CO(1−0) at the position of the AGN. Thus, in PKS 1549−79 we see the co-existence of accretion and the ejection of gas. The line ratio CO(3−2)/CO(1−0) suggests that the gas in the circumnuclear-disc has both high densities and high kinetic temperatures. We estimate a mass outflow rate of at least 650 M⊙ yr−1. This massive outflow is confined to the inner region (r <  120 pc) of the galaxy, which suggests that the AGN drives the outflow. Considering the amount of molecular gas available in the central nuclear disc and the observed outflow rate, we estimate a time scale of ∼105 yr over which the AGN would be able to destroy the circumnuclear disc, although gas from the merger may come in from larger radii, rebuilding this disc at the same time. The AGN appears to self-regulate gas accretion to the centre and onto the super-massive black hole. Surprisingly, from a comparison with Hubble Space Telescope data, we find that the ionised gas outflow is more extended. Nevertheless, the warm outflow is about two orders of magnitude less massive than the molecular outflow. PKS 1549−79 does not seem to follow the scaling relation between bolometric luminosity and the relative importance of warm ionised and molecular outflows claimed to exist for other AGN. We argue that, although PKS 1549−79 hosts a powerful quasar nucleus and an ultra-fast outflow, the radio jet plays a significant role in producing the outflow, which creates a cocoon of disturbed gas that expands into the circumnuclear disc.


2019 ◽  
Vol 621 ◽  
pp. A83 ◽  
Author(s):  
R. Slater ◽  
N. M. Nagar ◽  
A. Schnorr-Müller ◽  
T. Storchi-Bergmann ◽  
C. Finlez ◽  
...  

Context. Tracing nuclear inflows and outflows in active galactic nuclei (AGNs), determining the mass of gas involved in them, and their impact on the host galaxy and nuclear black hole requires 3D imaging studies of both the ionized and molecular gas. Aims. We map the distribution and kinematics of molecular and ionized gas in a sample of active galaxies to quantify the nuclear inflows and outflows. Here, we analyze the nuclear kinematics of NGC 1566 via ALMA observations of the CO J:2-1 emission at 24 pc spatial and ∼2.6 km s−1 spectral resolution, and Gemini-GMOS/IFU observations of ionized gas emission lines and stellar absorption lines at similar spatial resolution, and 123 km s−1 of intrinsic spectral resolution. Methods. The morphology and kinematics of stellar, molecular (CO), and ionized ([N II]) emission lines are compared to the expectations from rotation, outflows, and streaming inflows. Results. While both ionized and molecular gas show rotation signatures, there are significant non-circular motions in the innermost 200 pc and along spiral arms in the central kpc (CO). The nucleus shows a double-peaked CO profile (full width at zero intensity of 200 km s−1), and prominent (∼80 km s−1) blue- and redshifted lobes are found along the minor axis in the inner arcseconds. Perturbations by the large-scale bar can qualitatively explain all features in the observed velocity field. We thus favor the presence of a molecular outflow in the disk with true velocities of ∼180 km s−1 in the nucleus and decelerating to 0 by ∼72 pc. The implied molecular outflow rate is 5.6 M⊙ yr−1, with this gas accumulating in the nuclear 2″ arms. The ionized gas kinematics support an interpretation of a similar but more spherical outflow in the inner 100 pc, with no signs of deceleration. There is some evidence of streaming inflows of ∼50 km s−1 along specific spiral arms, and the estimated molecular mass inflow rate, ∼0.1 M⊙ yr−1, is significantly higher than the SMBH accretion rate (ṁ = 4.8 × 10−5 M⊙ yr−1).


2020 ◽  
Vol 496 (1) ◽  
pp. 598-611
Author(s):  
G Chartas ◽  
E Davidson ◽  
M Brusa ◽  
C Vignali ◽  
M Cappi ◽  
...  

ABSTRACT We present Atacama Large Millimeter/submillimeter Array (ALMA) observations of the quadruply lensed z =  1.51 quasar HS 0810+2554 which provide useful insight on the kinematics and morphology of the CO molecular gas and the ∼ 2 mm-continuum emission in the quasar host galaxy. Lens modelling of the mm-continuum and the spectrally integrated CO(J = 3→2) images indicates that the source of the mm-continuum has an eccentricity of e ∼ 0.9 with a size of ∼1.6 kpc and the source of line emission has an eccentricity of e ∼ 0.7 with a size of ∼1 kpc. The spatially integrated emission of the CO(J = 2→1) and CO(J = 3→2) lines shows a triple peak structure with the outer peaks separated by Δv21 = 220 ± 19 km s−1 and Δv32 = 245 ± 28 km s−1, respectively, suggesting the presence of rotating molecular CO line emitting gas. Lensing inversion of the high spatial resolution images confirms the presence of rotation of the line emitting gas. Assuming a conversion factor of αCO = 0.8 M⊙ (K km s−1 pc2)−1 we find the molecular gas mass of HS 0810+2554 to be MMol = (5.2 ± 1.5)/μ32 × 1010 M⊙, where μ32 is the magnification of the CO(J = 3→2) emission. We report the possible detection, at the 3.0–4.7σ confidence level, of shifted CO(J = 3→2) emission lines of high-velocity clumps of CO emission with velocities up to 1702 km s−1. We find that the momentum boost of the large-scale molecular wind is below the value predicted for an energy-conserving outflow given the momentum flux observed in the small-scale ultrafast outflow.


2020 ◽  
Vol 497 (4) ◽  
pp. 5103-5117
Author(s):  
Guilherme S Couto ◽  
Thaisa Storchi-Bergmann ◽  
Aneta Siemiginowska ◽  
Rogemar A Riffel ◽  
Raffaella Morganti

ABSTRACT We investigate the ionized gas excitation and kinematics in the inner $4.3\, \times \, 6.2$ kpc2 of the merger radio galaxy 4C+29.30. Using optical integral field spectroscopy with the Gemini North Telescope, we present flux distributions, line-ratio maps, peak velocities and velocity dispersion maps as well as channel maps with a spatial resolution of $\approx\! 955\,$ pc. We observe high blueshifts of up to $\sim\! -650\,$$\rm km\, s^{-1}$ in a region ∼1 arcsec south of the nucleus (the southern knot – SK), which also presents high velocity dispersions ($\sim\! 250\,$$\rm km\, s^{-1}$), which we attribute to an outflow. A possible redshifted counterpart is observed north from the nucleus (the northern knot – NK). We propose that these regions correspond to a bipolar outflow possibly due to the interaction of the radio jet with the ambient gas. We estimate a total ionized gas mass outflow rate of $\dot{M}_{\mathrm{ out}} = 25.4 ^{+11.5 }_{ -7.5}\,$ M⊙ yr−1with a kinetic power of $\dot{E} = 8.1 ^{+10.7 }_{ -4.0} \times 10^{42}\,$ erg s−1, which represents $5.8 ^{+7.6 }_{ -2.9} {{\ \rm per\ cent}}$ of the active galactic nucleus (AGN) bolometric luminosity. These values are higher than usually observed in nearby active galaxies with the same bolometric luminosities and could imply a significant impact of the outflows in the evolution of the host galaxy. The excitation is higher in the NK – that correlates with extended X-ray emission, indicating the presence of hotter gas – than in the SK, supporting a scenario in which an obscuring dust lane is blocking part of the AGN radiation to reach the southern region of the galaxy.


2019 ◽  
Vol 15 (S359) ◽  
pp. 262-264
Author(s):  
Guilherme S. Couto ◽  
Thaisa Storchi-Bergmann ◽  
Aneta Siemiginowska ◽  
Rogemar A. Riffel

AbstractWe investigate the ionized gas excitation and kinematics in the inner 4.3 × 6.2 kpc2 of the merger radio galaxy 4C +29.30. Using optical integral field spectroscopy with the Gemini North Telescope, we find signatures of gas outflows, including high blueshifts of up to ∼−650 km s−1 observed in a region ∼1″ south of the nucleus, which also presents high velocity dispersion (∼250 km s−1). A possible redshifted counterpart is observed north from the nucleus. We propose that these regions correspond to a bipolar outflow possibly due to the interaction of the radio jet with the ambient gas. We estimate a total ionized gas mass outflow rate of $\[{\dot M_{out}}&#x2009;=&#x2009;18.1\begin{array}{c}&#x2009;+&#x2009;8.2\\ - 5.3\end{array}{\kern 1pt} {\kern 1pt} \]$ with a kinetic power of $\[\dot E&#x2009;=&#x2009;5.8\begin{array}{c}&#x2009;+&#x2009;7.6\\ - 2.9\end{array} \times {10^{42}}{\kern 1pt} {\kern 1pt} \]$ , which represents $\[3.9\begin{array}{c}&#x2009;+&#x2009;5.1\\ - 1.5\end{array}\% \]$ of the AGN bolometric luminosity. These values are higher than usually observed in nearby active galaxies and could imply a significant impact of the outflows on the evolution of the host galaxy.


2021 ◽  
Vol 923 (1) ◽  
pp. 83
Author(s):  
Alberto D. Bolatto ◽  
Adam K. Leroy ◽  
Rebecca C. Levy ◽  
David S. Meier ◽  
Elisabeth A. C. Mills ◽  
...  

Abstract We present the ALMA detection of molecular outflowing gas in the central regions of NGC 4945, one of the nearest starbursts and also one of the nearest hosts of an active galactic nucleus (AGN). We detect four outflow plumes in CO J = 3 − 2 at ∼0.″3 resolution that appear to correspond to molecular gas located near the edges of the known ionized outflow cone and its (unobserved) counterpart behind the disk. The fastest and brightest of these plumes has emission reaching observed line-of-sight projected velocities of over 450 km s−1 beyond systemic, equivalent to an estimated physical outflow velocity v ≳ 600 km s−1 for the fastest emission. Most of these plumes have corresponding emission in HCN or HCO+ J = 4 − 3. We discuss a kinematic model for the outflow emission where the molecular gas has the geometry of the ionized gas cone and shares the rotation velocity of the galaxy when ejected. We use this model to explain the velocities we observe, constrain the physical speed of the ejected material, and account for the fraction of outflowing gas that is not detected due to confusion with the galaxy disk. We estimate a total molecular mass outflow rate M ̇ mol ∼ 20 M ⊙ yr−1 flowing through a surface within 100 pc of the disk midplane, likely driven by a combination of the central starburst and AGN.


2016 ◽  
Vol 12 (S324) ◽  
pp. 231-234
Author(s):  
Martin A. Bourne

AbstractFeedback released during the growth of supermassive black holes is expected to play a key role in shaping black hole-host galaxy co-evolution. Powerful, accretion disc driven winds have been invoked to explain both observed scaling relations (e.g., M − σ) and large-scale outflows with mass outflow rates of ~ 100 − 1000 M⊙ yr−1 and momentum rates of up to ~ 30 LAGN/c. Critically, how these winds couple to the host galaxy depends on if they are momentum or energy conserving. I outline observational signatures that could distinguish between these regimes and discuss their roles in establishing galaxy properties. Furthermore, I discuss high-resolution simulations exploring feedback in a multi-phase medium, highlighting how structural properties of galaxies can impact feedback efficiency. Finally, feedback, in the form of collimated jets, is expected to regulate cooling in galaxy clusters. I discuss new simulations of jet feedback using the moving-mesh code AREPO and outline the scope of our new study.


2020 ◽  
Vol 15 (S359) ◽  
pp. 243-248
Author(s):  
Raffaella Morganti ◽  
Tom Oosterloo ◽  
Clive N. Tadhunter

AbstractWe present an update of our ongoing project to characterise the impact of radio jets on the interstellar medium (ISM). This is done by tracing the distribution, kinematics and excitation of the molecular gas at high spatial resolution using ALMA. The radio active galactic nuclei (AGN) studied are in the interesting phase of having a recently born radio jet. In this stage, the plasma jets can have the largest impact on the ISM, as also predicted by state-of-the-art simulations. The two targets we present have quite different ages, allowing us to get snapshots of the effects of radio jets as they grow and evolve. Interestingly, both also host powerful quasar emission, making them ideal for studying the full impact of AGN. The largest mass outflow rate of molecular gas is found in a radio galaxy () hosting a newly born radio jet still in the early phase of emerging from an obscuring cocoon of gas and dust. Although the molecular mass outflow rate is high (few hundred), the outflow is limited to the inner few hundred pc region. In a second object (), the jet is larger (a few kpc) and is in a more advanced evolutionary phase. In this object, the distribution of the molecular gas is reminiscent of what is seen, on larger scales, in cool-core clusters hosting radio galaxies. Interestingly, gas deviating from quiescent kinematics (possibly indicating an outflow) is not very prominent, limited only to the very inner region, and has a low mass outflow rate. Instead, on kpc scales, the radio lobes appear associated with depressions in the distribution of the molecular gas. This suggests that the lobes have broken out from the dense nuclear region. However, the AGN does not appear to be able, at present, to stop the star formation observed in this galaxy. These results support the idea that the effects of the radio source start in the very first phases by producing outflows which, however, tend to be limited to the kpc region. After that, the effects turn into producing large-scale bubbles which could, in the long term, prevent the surrounding gas from cooling. Thus, our results provide a way to characterise the effect of radio jets in different phases of their evolution and in different environments, bridging the studies done for radio galaxies in clusters.


2019 ◽  
Vol 630 ◽  
pp. A59 ◽  
Author(s):  
M. Bischetti ◽  
R. Maiolino ◽  
S. Carniani ◽  
F. Fiore ◽  
E. Piconcelli ◽  
...  

We present the stacking analysis of a sample of 48 quasi-stellar objects (QSOs) at 4.5 <  z <  7.1 detected by the Atacama Large Millimetre Array (ALMA) in the [CII] λ158 μm emission line to investigate the presence and the properties of massive, cold outflows associated with broad wings in the [CII] profile. The high sensitivity reached through this analysis allows us to reveal very broad [CII] wings tracing the presence of outflows with velocities in excess of 1000 km s−1. We find that the luminosity of the broad [CII] emission increases with LAGN, while it does not significantly depend on the star formation rate of the host galaxy, indicating that the central active galactic nucleus (AGN) is the main driving mechanism of the [CII] outflows in these powerful, distant QSOs. From the stack of the ALMA cubes, we derive an average outflow spatial extent of ∼3.5 kpc. The average atomic neutral mass outflow rate inferred from the stack of the whole sample is Ṁout ∼ 100 M⊙ yr−1, while for the most luminous systems it increases to ∼200 M⊙ yr−1. The associated outflow kinetic power is about 0.1% of LAGN, while the outflow momentum rate is ∼LAGN/c or lower, suggesting that these outflows are either driven by radiation pressure onto dusty clouds or, alternatively, are driven by the nuclear wind and energy conserving but with low coupling with the interstellar medium. We discuss the implications of the resulting feedback effect on galaxy evolution in the early Universe.


Sign in / Sign up

Export Citation Format

Share Document