Deep and narrow CO absorption revealing molecular clouds in the Hydra-A brightest cluster galaxy

Abstract

Active galactic nuclei play a crucial role in the accretion and ejection of gas in galaxies. Although their outflows are well studied, finding direct evidence of accretion has proved very difficult and has so far been done for very few sources. A promising way to study the significance of cold accretion is by observing the absorption of an active galactic nucleus's extremely bright radio emission by the cold gas lying along the line-of-sight. As such, we present ALMA CO(1-0) and CO(2-1) observations of the Hydra-A brightest cluster galaxy (z=0.054) which reveal the existence of cold, molecular gas clouds along the line-of-sight to the galaxy's extremely bright and compact mm-continuum source. They have apparent motions relative to the central supermassive black hole of between -43 and -4 km s${}^{-1}$ and are most likely moving along stable, low ellipticity orbits. The identified clouds form part of a $\sim$$10^9$ ${\text{M}}_{\odot }$, approximately edge-on disc of cold molecular gas. With peak CO(2-1) optical depths of $\tau$=0.88 ${}_{-0.06}^{+0.06}$, they include the narrowest and by far the deepest absorption of this type which has been observed to date in a brightest cluster galaxy. By comparing the relative strengths of the lines for the most strongly absorbing region, we are able to estimate a gas temperature of $42_{-11}^{+25}$ K and line-of-sight column densities of $N_{CO}=2_{-1}^{+3}\times 10^{17}c{m}^{-2}$ and $N_{H_2}=7_{-4}^{+10}\times 10^{20}c{m}^{-2}$.

arXiv comment11 pages, 8 figures, accepted to MNRAS

References in corpus (44)

• The many lives of active galactic nuclei: cooling flows, black holes and the luminosities and colours of galaxies
• The broken hierarchy of galaxy formation
• The CO-to-H2 Conversion Factor
• Evolution of Buoyant Bubbles in M87
• Powerful Outflows and Feedback from Active Galactic Nuclei
• Mechanical Feedback from Active Galactic Nuclei in Galaxies, Groups, and Clusters
• Chandra X-ray Observations of the Hydra A Cluster: An Interaction Between the Radio Source and the X-Ray-Emitting Gas
• Molecular line emission in NGC1068 imaged with ALMA. I An AGN-driven outflow in the dense molecular gas
• Chaotic cold accretion onto black holes
• The ROSAT Brightest Cluster Sample (BCS): -- III. Optical spectra of the central cluster galaxies
• How to Calculate Molecular Column Density
• The detection of molecular gas in the central galaxies of cooling-flow clusters
• Cold molecular gas in cooling flow clusters of galaxies
• Interstellar Carbon in Translucent Sightlines
• The cluster-scale AGN outburst in Hydra A
• On the Nature of Feedback Heating in Cooling Flow Clusters
• Raining on black holes and massive galaxies: the top-down multiphase condensation model
• X-ray Supercavities in the Hydra A Cluster and the Outburst History of the Central Galaxy's Active Nucleus
• ALMA observations of feeding and feedback in nearby Seyfert galaxies: an AGN-driven outflow in NGC 1433
• Cold, clumpy accretion onto an active supermassive black hole
• Radiative efficiency, variability and Bondi accretion onto massive black holes: from mechanical to quasar feedback in brightest cluster galaxies
• Accretion of low angular momentum material onto black holes: 2D magnetohydrodynamical case
• The Dance of Heating and Cooling in Galaxy Clusters: 3D Simulations of Self-Regulated AGN Outflows
• Shaken Snow Globes: Kinematic Tracers of the Multiphase Condensation Cascade in Massive Galaxies, Groups, and Clusters
• A Mechanism for Stimulating AGN Feedback by Lifting Gas in Massive Galaxies
• Chaotic cold accretion on to black holes in rotating atmospheres
• A survey of molecular hydrogen in the central galaxies of cooling flows
• A Galaxy-Scale Fountain of Cold Molecular Gas Pumped by a Black Hole
• A very extended molecular web around NGC 1275
• Molecular absorption lines toward star-forming regions : a comparative study of HCO+, HNC, HCN, and CN
• Molecular Gas in the X-ray Bright Group NGC 5044 as Revealed by ALMA
• Pahs, Ionized Gas, and Molecular Hydrogen in Brightest Cluster Galaxies of Cool Core Clusters of Galaxies
• ALMA observations of molecular clouds in three group centered elliptical galaxies: NGC 5846, NGC 4636, and NGC 5044
• Solving the angular momentum problem in the cold feedback mechanism of cooling flows
• HII and H2 in the envelopes of cooling flow central galaxies
• Unusual CO Line Ratios and kinematics in the N83/N84 Region of the Small Magellanic Cloud
• A Large Mass of H2 in the Brightest Cluster Galaxy in Zwicky 3146
• Herschel photometry of brightest cluster galaxies in cooling flow clusters
• Cold gas dynamics in Hydra-A: evidence for a rotating disk
• High Radio Frequency Properties and Variability of Brightest Cluster Galaxies
• Infrared Spectra of Cooling Flow Galaxies
• Molecular Gas in the Powerful Radio Galaxies 3C~31 and 3C~264: Major or Minor Mergers?
• Constraining star formation rates in cool-core brightest cluster galaxies
• ALMA Observations of Molecular Absorption in the Gravitational Lens PMN 0134-0931

Cited by in corpus (21)

• Resolving small-scale cold circumgalactic gas in TNG50
• Ubiquitous cold and massive filaments in cool core clusters
• Driving massive molecular gas flows in central cluster galaxies with AGN feedback
• Constraining cold accretion onto supermassive black holes: molecular gas in the cores of eight brightest cluster galaxies revealed by joint CO and CN absorption
• Black Hole Mass Measurements of Radio Galaxies NGC 315 and NGC 4261 Using ALMA CO Observations
• The ALMA Discovery of the Rotating Disk and Fast Outflow of Cold Molecular Gas in NGC 1275
• ALMACAL VI: Molecular gas mass density across cosmic time via a blind search for intervening molecular absorbers
• Gas condensation in Brightest Group Galaxies unveiled with MUSE
• The Dust and Molecular Gas in the Brightest Cluster Galaxy in MACS 1931.8-2635
• A molecular absorption line survey toward the AGN of Hydra-A
• Atacama Compact Array Measurements of the Molecular Mass in the NGC 5044 Cooling Flow Group
• Molecular Flows in Contemporary Active Galaxies and the Efficacy of Radio-Mechanical Feedback
• Does absorption against AGN reveal supermassive black hole accretion?
• The variability of brightest cluster galaxies at high radio frequencies
• Hard X-ray Irradiation Potentially Drives Negative AGN Feedback by Altering Molecular Gas Properties
• A Massive, Clumpy Molecular Gas Distribution and Displaced AGN in Zw 3146
• Circumnuclear Medium around the Central AGN in a Cool-Core Cluster, Abell 1644-South
• The correlation between the 500 pc scale molecular gas masses and AGN powers for massive elliptical galaxies
• Constraining Radio Mode Feedback in Galaxy Clusters with the Cluster Radio AGN Properties to z$\sim$1
• A 4~Kpc Molecular Gas Lane in Cygnus A
• Chasing ICM cooling and AGN feedback from the macro to the meso scales in the galaxy cluster ZwCl 235