scholarly journals WISDOM project – IV. A molecular gas dynamical measurement of the supermassive black hole mass in NGC 524

2019 ◽  
Vol 485 (3) ◽  
pp. 4359-4374 ◽  
Author(s):  
Mark D Smith ◽  
Martin Bureau ◽  
Timothy A Davis ◽  
Michele Cappellari ◽  
Lijie Liu ◽  
...  
Keyword(s):  
Black Hole ◽  
Gas Flow ◽  
Line Emission ◽  
Position Angle ◽  
High Angular Resolution ◽  
Molecular Gas ◽  
Continuum Source ◽  
Supermassive Black Hole ◽  
Sphere Of Influence ◽  
Dynamical Measurement

ABSTRACT We present high angular resolution (0.3 arcsec or $37\, \mathrm{pc}$) Atacama Large Millimeter/submillimeter Array observations of the CO(2–1) line emission from a central disc in the early-type galaxy NGC 524. This disc is shown to be dynamically relaxed, exhibiting ordered rotation about a compact $1.3\, \mathrm{mm}$ continuum source, which we identify as emission from an active supermassive black hole (SMBH). There is a hole at the centre of the disc slightly larger than the SMBH sphere of influence. An azimuthal distortion of the observed velocity field is found to be due to either a position angle warp or radial gas flow over the inner 2${^{\prime\prime}_{.}}$5. By forward-modelling the observations, we obtain an estimate of the SMBH mass of $4.0^{+3.5}_{-2.0}\times 10^8\,$ M⊙, where the uncertainties are at the 3σ level. The uncertainties are dominated by the poorly constrained inclination and the stellar mass-to-light ratio of this galaxy, and our measurement is consistent with the established correlation between SMBH mass and stellar velocity dispersion. Our result is roughly half that of the previous stellar dynamical measurement, but is consistent within the uncertainties of both. We also present and apply a new tool for modelling complex molecular gas distributions.

scholarly journals WISDOM project – V. Resolving molecular gas in Keplerian rotation around the supermassive black hole in NGC 0383

2019 ◽  
Vol 490 (1) ◽  
pp. 319-330 ◽  
Author(s):  
Eve V North ◽  
Timothy A Davis ◽  
Martin Bureau ◽  
Michele Cappellari ◽  
Satoru Iguchi ◽  
...  
Keyword(s):  
Black Hole ◽  
Velocity Dispersion ◽  
Outer Edge ◽  
Data Cube ◽  
Continuum Emission ◽  
Molecular Gas ◽  
Supermassive Black Hole ◽  
Sphere Of Influence ◽  
Early Type Galaxy ◽  
Co Emission

ABSTRACT As part of the mm-Wave Interferometric Survey of Dark Object Masses (WISDOM), we present a measurement of the mass of the supermassive black hole (SMBH) in the nearby early-type galaxy NGC 0383 (radio source 3C 031). This measurement is based on Atacama Large Millimeter/sub-millimeter Array (ALMA) cycle 4 and 5 observations of the 12CO(2–1) emission line with a spatial resolution of 58 × 32 pc2 (0.18 arcsec × 0.1 arcsec). This resolution, combined with a channel width of 10 km s−1, allows us to well resolve the radius of the black hole sphere of influence (measured as RSOI = 316 pc  =  0.98 arcsec), where we detect a clear Keplerian increase of the rotation velocities. NGC 0383 has a kinematically relaxed, smooth nuclear molecular gas disc with weak ring/spiral features. We forward model the ALMA data cube with the Kinematic Molecular Simulation (KinMS) tool and a Bayesian Markov Chain Monte Carlo method to measure an SMBH mass of (4.2 ± 0.7) × 109 M⊙, a F160W-band stellar mass-to-light ratio that varies from 2.8 ± 0.6 M⊙/L$_{\odot ,\, \mathrm{F160W}}$ in the centre to 2.4 ± 0.3 M⊙$/\rm L_{\odot ,\, \mathrm{F160W}}$ at the outer edge of the disc and a molecular gas velocity dispersion of 8.3 ± 2.1 km s−1(all 3σ uncertainties). We also detect unresolved continuum emission across the full bandwidth, consistent with synchrotron emission from an active galactic nucleus. This work demonstrates that low-J CO emission can resolve gas very close to the SMBH ($\approx 140\, 000$ Schwarzschild radii) and hence that the molecular gas method is highly complimentary to megamaser observations, as it can probe the same emitting material.

Central kiloparsec of NGC 1326 observed with SINFONI

2020 ◽  
Vol 638 ◽  
pp. A53
Author(s):  
Nastaran Fazeli ◽  
Gerold Busch ◽  
Andreas Eckart ◽  
Françoise Combes ◽  
Persis Misquitta ◽  
...  
Keyword(s):  
Black Hole ◽  
Galaxy Evolution ◽  
Near Infrared ◽  
Velocity Fields ◽  
Molecular Gas ◽  
Nearby Galaxy ◽  
Stellar Content ◽  
Stellar Rotation ◽  
Supermassive Black Hole ◽  
Integral Field Spectrograph

Gas inflow processes in the vicinity of galactic nuclei play a crucial role in galaxy evolution and supermassive black hole growth. Exploring the central kiloparsec of galaxies is essential to shed more light on this subject. We present near-infrared H- and K-band results of the nuclear region of the nearby galaxy NGC 1326, observed with the integral-field spectrograph SINFONI mounted on the Very Large Telescope. The field of view covers 9″ × 9″ (650 × 650 pc2). Our work is concentrated on excitation conditions, morphology, and stellar content. The nucleus of NGC 1326 was classified as a LINER, however in our data we observed an absence of ionised gas emission in the central r ∼ 3″. We studied the morphology by analysing the distribution of ionised and molecular gas, and thereby detected an elliptically shaped, circum-nuclear star-forming ring at a mean radius of 300 pc. We estimate the starburst regions in the ring to be young with dominating ages of < 10 Myr. The molecular gas distribution also reveals an elongated east to west central structure about 3″ in radius, where gas is excited by slow or mild shock mechanisms. We calculate the ionised gas mass of 8 × 105 M⊙ completely concentrated in the nuclear ring and the warm molecular gas mass of 187 M⊙, from which half is concentrated in the ring and the other half in the elongated central structure. The stellar velocity fields show pure rotation in the plane of the galaxy. The gas velocity fields show similar rotation in the ring, but in the central elongated H2 structure they show much higher amplitudes and indications of further deviation from the stellar rotation in the central 1″ aperture. We suggest that the central 6″ elongated H2 structure might be a fast-rotating central disc. The CO(3–2) emission observations with the Atacama Large Millimeter/submillimeter Array reveal a central 1″ torus. In the central 1″ of the H2 velocity field and residual maps, we find indications for a further decoupled structure closer to a nuclear disc, which could be identified with the torus surrounding the supermassive black hole.

scholarly journals WISDOM project – VII. Molecular gas measurement of the supermassive black hole mass in the elliptical galaxy NGC 7052

2021 ◽  
Vol 503 (4) ◽  
pp. 5984-5996
Author(s):  
Mark D Smith ◽  
Martin Bureau ◽  
Timothy A Davis ◽  
Michele Cappellari ◽  
Lijie Liu ◽  
...  
Keyword(s):  
Black Hole ◽  
Hubble Space Telescope ◽  
Elliptical Galaxy ◽  
Continuum Emission ◽  
Molecular Gas ◽  
Supermassive Black Hole ◽  
Gas Kinematics ◽  
Long Baseline ◽  
Gas Measurement ◽  
Strong Gradient

ABSTRACT Supermassive black hole (SMBH) masses can be measured by resolving the dynamical influences of the SMBHs on tracers of the central potentials. Modern long-baseline interferometers have enabled the use of molecular gas as such a tracer. We present here Atacama Large Millimeter/submillimeter Array observations of the elliptical galaxy NGC 7052 at 0${^{\prime\prime}_{.}}$11 ($37\,$pc) resolution in the 12CO(2-1) line and $1.3\,$ mm continuum emission. This resolution is sufficient to resolve the region in which the potential is dominated by the SMBH. We forward model these observations, using a multi-Gaussian expansion of a Hubble Space Telescope F814W image and a spatially constant mass-to-light ratio to model the stellar mass distribution. We infer an SMBH mass of $2.5\pm 0.3\times 10^{9}\, \mathrm{M_\odot }$ and a stellar I-band mass-to-light ratio of $4.6\pm 0.2\, \mathrm{M_\odot /L_{\odot ,I}}$ (3σ confidence intervals). This SMBH mass is significantly larger than that derived using ionized gas kinematics, which however appears significantly more kinematically disturbed than the molecular gas. We also show that a central molecular gas deficit is likely to be the result of tidal disruption of molecular gas clouds due to the strong gradient in the central gravitational potential.

Radio continuum of galaxies with H2O megamaser disks

2017 ◽  
Vol 13 (S336) ◽  
pp. 139-140
Author(s):  
F. Kamali ◽  
C. Henkel ◽  
A. Brunthaler ◽  
C. M. V. Impellizzeri ◽  
K. M. Menten ◽  
...  
Keyword(s):  
Black Hole ◽  
Accretion Disk ◽  
Active Galactic Nucleus ◽  
Position Angle ◽  
Radio Continuum ◽  
Supermassive Black Hole ◽  
5 Ghz

AbstractIn our attempt to investigate the basic active galactic nucleus (AGN) paradigm requiring a centrally located supermassive black hole (SMBH), a close to Keplerian accretion disk and a jet perpendicular to its plane, we have searched for radio continuum in galaxies with H2O megamasers in their disks. We observed 18 such galaxies with the Very Large Baseline Array in C band (5 GHz, ~2 mas resolution) and we detected 5 galaxies at 8 σ or higher levels. For those sources for which the maser data is available, the positions of masers and those of the 5 GHz radio continuum sources coincide within the uncertainties, and the radio continuum is perpendicular to the maser disk’s orientation within the position angle uncertainties.

scholarly journals WISDOM Project – III. Molecular gas measurement of the supermassive black hole mass in the barred lenticular galaxy NGC4429

2017 ◽  
Vol 473 (3) ◽  
pp. 3818-3834 ◽  
Author(s):  
Timothy A. Davis ◽  
Martin Bureau ◽  
Kyoko Onishi ◽  
Freeke van de Voort ◽  
Michele Cappellari ◽  
...  
Keyword(s):  
Black Hole ◽  
Molecular Gas ◽  
Black Hole Mass ◽  
Supermassive Black Hole ◽  
Gas Measurement

scholarly journals WISDOM Project – II. Molecular gas measurement of the supermassive black hole mass in NGC 4697

2017 ◽  
Vol 468 (4) ◽  
pp. 4675-4690 ◽  
Author(s):  
Timothy A. Davis ◽  
Martin Bureau ◽  
Kyoko Onishi ◽  
Michele Cappellari ◽  
Satoru Iguchi ◽  
...  
Keyword(s):  
Black Hole ◽  
Molecular Gas ◽  
Black Hole Mass ◽  
Supermassive Black Hole ◽  
Gas Measurement

scholarly journals Gas Dynamics in AGN Galaxies: First Results of the HI-NUGA Survey

2006 ◽  
Vol 2 (S235) ◽  
pp. 101-101
Author(s):  
S. Haan ◽  
E. Schinnerer ◽  
C.G. Mundell ◽  
S. García-Burillo ◽  
F. Combes
Keyword(s):  
Black Hole ◽  
Gas Flow ◽  
Line Emission ◽  
Imaging Data ◽  
Gas Distribution ◽  
Central Black Hole ◽  
Very Large Array ◽  
Array Configuration ◽  
First Results ◽  
Minor Mergers

AbstractThe process of fueling Active Galactic Nuclei (AGN) in galaxies is commonly associated with gas aggregation onto a central supermassive black hole. Up to now a general picture of the AGN fueling is missing: What mechanisms are responsible for the various kinds of AGNs? How to remove angular momentum from the material far away from the gravitational influence of the central black hole? Over the last decade observations have been pointing towards a hierarchy of mechanisms that all combine to transport the gas from the large kpc scales down to the inner pc scales. In addition, fueling mechanisms excited by the galactic environment, e.g. through minor mergers and tidal interactions, have been suggested.In order to study the gas transport from the outskirts of galaxies to the central AGN, we have embarked on a key project, NUGA (Nuclei of Galaxies): a high spectral and angular resolution CO and HI survey of low luminosity AGN in nearby galaxies (i.e. Seyferts, LINERs and transition objects).For our detailed HI study, 16 nearby AGN galaxies were observed in their 21 cm line emission of neutral HI gas using the NRAO Very Large Array (VLA) interferometer in its C- and D-array configuration (~20'' angular and ~5.2 km s−1 spectral resolution). The spiral galaxies in our sample range in Hubble type from Sa to Sbc. For all galaxies high quality mm-interferometric CO data as well as optical/NIR imaging data are available.Here, we present first results on the atomic gas distribution and kinematics in these galaxies: The HI gas properties are analyzed and then compared to the optical properties. Their HI morphology reveals a wide variety: rings, spiral arms, and central concentrated, where ring structures are mostly found in LINER hosts. The integrated surface brightness profiles show some significant differences between the HI gas and stellar light as well as their radial extent. Our analysis of the HI environment yields that 4 galaxies are surrounded by satellites and 8 galaxies have disturbed outer HI disks, probably due to ram pressure stripping and/or minor mergers. Our analysis of the HI kinematics provides rotation curves, dynamical masses and evidence for streaming motions for each galaxy.The inclusion of recently obtained VLA B-array data will provide ~7″ resolution for more than half of the sample. We will utilize gravity torques based on a definite phase shift between the gravitational potential and the HI gas distribution to determine the gas inflow, and thus the efficiency for feeding the central black hole. Further, the combined CO+HI+NIR/opt data will allow us to develop dynamical models describing the gas flow in galactic disks from the large kpc scales down to the inner pc scales for selected galaxies in our sample.

scholarly journals Explaining temporal variations in the jet position angle of the blazar OJ 287 using its binary black hole central engine model

2021 ◽  
Author(s):  
Lankeswar Dey ◽  
Mauri J Valtonen ◽  
A Gopakumar ◽  
Rocco Lico ◽  
José L Gómez ◽  
...  
Keyword(s):  
Black Hole ◽  
Position Angle ◽  
Temporal Variations ◽  
Optical Observations ◽  
High Angular Resolution ◽  
Orbital Parameters ◽  
Engine Model ◽  
Binary Black Hole ◽  
Central Engine ◽  
Blazar Oj 287

Abstract The bright blazar OJ 287 is the best-known candidate for hosting a supermassive black hole binary system. It inspirals due to the emission of nanohertz gravitational waves (GWs). Observations of historical and predicted quasi-periodic high-brightness flares in its century-long optical lightcurve, allow us to determine the orbital parameters associated with the binary black hole (BBH) central engine. In contrast, the radio jet of OJ 287 has been covered with Very Long Baseline Interferometry (VLBI) observations for only about 30 years and these observations reveal that the position angle (PA) of the jet exhibits temporal variations at both millimetre and centimetre wavelengths. Here we associate the observed PA variations in OJ 287 with the precession of its radio jet. In our model, the evolution of the jet direction can be associated either with the primary black hole (BH) spin evolution or with the precession of the angular momentum direction of the inner region of the accretion disc. Our Bayesian analysis shows that the BBH central engine model, primarily developed from optical observations, can also broadly explain the observed temporal variations in the radio jet of OJ 287 at frequencies of 86, 43, and 15 GHz. Ongoing Global mm-VLBI Array (GMVA) observations of OJ 287 have the potential to verify our predictions for the evolution of its 86 GHz PA values. Additionally, thanks to the extremely high angular resolution that the Event Horizon Telescope (EHT) can provide, we explore the possibility to test our BBH model through the detection of the jet in the secondary black hole .

scholarly journals Estimating supermassive black hole masses in active galactic nuclei using polarization of broad Mg ii, H α, and H β lines

2020 ◽  
Vol 497 (3) ◽  
pp. 3047-3054
Author(s):  
Đorđe Savić ◽  
L Č Popović ◽  
E Shablovinskaya ◽  
V L Afanasiev
Keyword(s):  
Black Hole ◽  
Active Galactic Nuclei ◽  
Three Dimensional ◽  
Polarization Plane ◽  
Galactic Nuclei ◽  
Position Angle ◽  
Broad Line ◽  
Keplerian Motion ◽  
Supermassive Black Hole ◽  
Polarization Mechanism

ABSTRACT For type-1 active galactic nuclei (AGNs) for which the equatorial scattering is the dominant broad-line polarization mechanism, it is possible to measure the supermassive black hole (SMBH) mass by tracing the Keplerian motion across the polarization plane position angle φ. So far, this method has been used for 30 objects but only for H α emission line. We explore the possibilities of this method for determining SMBH masses using polarization in broad emission lines by applying it for the first time to Mg ii λ2798 Å spectral line. We use three-dimensional (3-D) Monte Carlo radiative transfer code stokes for simultaneous modelling of equatorial scattering of H α, H β, and Mg ii lines. We included vertical inflows and outflows in the Mg ii broad-line region (BLR). We find that polarization states of H α and H β lines are almost identical and SMBH-mass estimates differ by 7 per cent. For Mg ii line, we find that φ exhibits an additional ‘plateau’ with a constant φ, which deviates than the profiles expected for pure Keplerian motion. SMBH-mass estimates using Mg ii line are higher by up to 35 per cent than those obtained from H α and H β lines. Our model shows that for vertical inflows and outflows in the BLR that are higher or comparable to the Keplerian velocity, this method can be applied as a first approximation for obtaining SMBH mass.

scholarly journals η Carinae: high angular resolution continuum, H30α and He30α ALMA images

2020 ◽  
Vol 499 (2) ◽  
pp. 2493-2512
Author(s):  
Zulema Abraham ◽  
Pedro P B Beaklini ◽  
Pierre Cox ◽  
Diego Falceta-Gonçalves ◽  
Lars-Åke Nyman
Keyword(s):  
Angular Resolution ◽  
Line Emission ◽  
High Angular Resolution ◽  
Proper Motions ◽  
Recombination Line ◽  
Compact Source ◽  
Continuum Source ◽  
Velocity Images ◽  
First Time ◽  
Compact Sources

ABSTRACT We present images of η Carinae in the recombination lines H30α and He30α and the underlying continuum with 50 mas resolution (110 au), obtained with ALMA. For the first time, the 230 GHz continuum image is resolved into a compact core, coincident with the binary system position, and a weaker extended structure to the NW of the compact source. Iso-velocity images of the H30α recombination line show at least 16 unresolved sources with velocities between −30 and −65 km s−1 distributed within the continuum source. A NLTE model, with density and temperature of the order of 107 cm−3 and 104 K, reproduce both the observed H30α line profiles and their underlying continuum flux densities. Three of these sources are identified with Weigelt blobs D, C, and B; estimating their proper motions, we derive ejection times (in years) of 1952.6, 1957.1, and 1967.6, respectively, all of which are close to periastron passage. Weaker H30α line emission is detected at higher positive and negative velocities, extending in the direction of the Homunculus axis. The He30α recombination line is also detected with the same velocity of the narrow H30α line. Finally, the close resemblance of the H30α image with that of an emission line that was reported in the literature as HCO+(4–3) led us to identify this line as H40δ instead, an identification that is further supported by modelling results. Future observations will enable to determine the proper motions of all the compact sources discovered in the new high angular resolution data of η Carinae.

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