Radio-loud active galactic nuclei (RLAGNs) are a unique AGN population and were thought to be preferentially associated with supermassive black holes (SMBHs) at low accretion rates. They could impact the host galaxy evolution by expelling cold gas through the jet-mode feedback. In this work, we studied CO(6−5) line emission and continuum emission in a high-redshift radio galaxy, MRC 0152−209, at z = 1.92 using ALMA (Atacama Large Millimeter/submillimeter Array) up to a 0.024″ resolution (corresponding to ∼200 pc at z = 1.92). This system is a starburst major merger comprising two galaxies: the north-west (NW) galaxy hosting the RLAGN with jet kinetic power Ljet ≳ 2 × 1046 erg s−1 and the other galaxy to the south-east (SE). Based on the spectral energy distribution fitting for the entire system (NW+SE galaxies), we find an AGN bolometric luminosity LAGN, bol ∼ 3 × 1046 erg s−1 with a lower limit of ∼0.9 × 1046 erg s−1 for the RLAGN. We estimate the black hole mass through MBH–M⋆ scaling relations and find an Eddington ratio of λEdd ∼ 0.07–4 conservatively by adopting the lower limit of LAGN, bol and considering the dispersion of the scaling relation. These results suggest that the RLAGN is radiatively efficient and the powerful jets could be launched from a super-Eddington accretion disc. ALMA Cycle 6 observations further reveal a massive (${M}_\mathrm{H_2}=(1.1-2.3)\times 10^9\ \rm M_\odot$), compact (∼500 pc), and monopolar molecular outflow perpendicular to the jet axis. The corresponding mass outflow rate ($1200^{+300}_{-300}-2600^{+600}_{-600}\ \mathrm{M_\odot }\ \rm yr^{-1}$) is comparable with the star formation rate of at least $\sim 2100\ \mathrm{M_\odot }\ \rm yr^{-1}$. Depending on the outflowing molecular gas mass, the outflow kinetic power/LAGN, bol ratio of ∼0.008–0.02, and momentum boost factor of ∼3–24 agree with a radiative-mode AGN feedback scenario. On the other hand, the jets can also drive the molecular outflow within its lifetime of ∼2 × 105 yr without additional energy supply from AGN radiation. The jet-mode feedback is then capable of removing all cold gas from the host galaxy through the long-term, episodic launching of jets. Our study reveals a unique object where starburst activity, powerful jets, and rapid BH growth co-exist, which may represent a fundamental stage of AGN-host galaxy co-evolution.
We present the deepest Chandra observation to date of the galaxy M84 in the Virgo Cluster, with over 840 ks of data provided by legacy observations and a recent 730 ks campaign. The increased signal-to-noise ratio allows us to study the origins of the accretion flow feeding the supermassive black hole in the centre of M84 from the kiloparsec scales of the X-ray halo to the Bondi radius, RB. Temperature, metallicity, and deprojected density profiles are obtained in four sectors about M84’s active galactic nucleus (AGN), extending into the Bondi radius. Rather than being dictated by the potential of the black hole, the accretion flow is strongly influenced by the AGN’s bipolar radio jets. Along the jet axis, the density profile is consistent with ne ∝ r−1; however, the profiles flatten perpendicular to the jet. Radio jets produce a significant asymmetry in the flow, violating a key assumption of Bondi accretion. Temperature in the inner kiloparsec is approximately constant, with only a slight increase from 0.6 to 0.7 keV approaching RB, and there is no evidence for a temperature rise imposed by the black hole. The Bondi accretion rate $\dot{M}_{\rm B}$ exceeds the rate inferred from AGN luminosity and jet power by over four orders of magnitude. In sectors perpendicular to the jet, $\dot{M}_{\rm B}$ measurements agree; however, the accretion rate is >4σ lower in the North sector along the jet, likely due to cavities in the X-ray gas. Our measurements provide unique insight into the fuelling of AGN responsible for radio mode feedback in galaxy clusters.
more » « less- NSF-PAR ID:
- 10412620
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Monthly Notices of the Royal Astronomical Society
- Volume:
- 522
- Issue:
- 3
- ISSN:
- 0035-8711
- Page Range / eLocation ID:
- p. 4374-4391
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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