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Title: Alma observations of massive molecular gas filaments encasing radio bubbles in the Phoenix cluster

We report new ALMA observations of the CO(3-2) line emission from the $$2.1\pm0.3\times10^{10}\rm\thinspace M_{\odot}$$ molecular gas reservoir in the central galaxy of the Phoenix cluster. The cold molecular gas is fuelling a vigorous starburst at a rate of $$500-800\rm\thinspace M_{\odot}\rm\; yr^{-1}$$ and powerful black hole activity in the form of both intense quasar radiation and radio jets. The radio jets have inflated huge bubbles filled with relativistic plasma into the hot, X-ray atmospheres surrounding the host galaxy. The ALMA observations show that extended filaments of molecular gas, each $$10-20\rm\; kpc$$ long with a mass of several billion solar masses, are located along the peripheries of the radio bubbles. The smooth velocity gradients and narrow line widths along each filament reveal massive, ordered molecular gas flows around each bubble, which are inconsistent with gravitational free-fall. The molecular clouds have been lifted directly by the radio bubbles, or formed via thermal instabilities induced in low entropy gas lifted in the updraft of the bubbles. These new data provide compelling evidence for close coupling between the radio bubbles and the cold gas, which is essential to explain the self-regulation of feedback. As a result, the very feedback mechanism that heats hot atmospheres and suppresses star formation may also paradoxically stimulate production of the cold gas required to sustain feedback in massive galaxies.
 [1] ; ORCiD logo [2] ; ORCiD logo [3] ;  [1] ; ORCiD logo [4] ; ORCiD logo [5] ;  [6] ; ORCiD logo [7] ;  [8] ; ORCiD logo [9] ; ORCiD logo [10] ; ORCiD logo [11] ; ORCiD logo [12] ; ORCiD logo [13]
  1. Institute of Astronomy, Cambridge (United Kingdom)
  2. Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
  3. Univ. of Waterloo, Waterloo, ON (Canada); Perimeter Institute for Theoretical Physics, Waterloo, ON (Canada)
  4. Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (United States); Univ. of Western Australia, Crawley, WA (Australia)
  5. Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Colby College, Waterville, ME (United States)
  6. Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Univ. of Chicago, Chicago, IL (United States)
  7. Univ. of Missouri, Kansas City, MO (United States)
  8. Univ. of Chicago, Chicago, IL (United States)
  9. Durham Univ., Durham (United Kingdom)
  10. Univ. de Montreal, Montreal, QC (Canada)
  11. Univ. of Arizona, Tucson, AZ (United States)
  12. Univ. of Melbourne, Parkville, VIC (Australia)
  13. Univ. of Illinois, Urbana, IL (United States)
Publication Date:
Report Number(s):
arXiv:1611.00017; FERMILAB-PUB-16-672-AE
Journal ID: ISSN 1538-4357; 1594856
Grant/Contract Number:
Accepted Manuscript
Journal Name:
The Astrophysical Journal (Online)
Additional Journal Information:
Journal Name: The Astrophysical Journal (Online); Journal Volume: 836; Journal Issue: 1; Journal ID: ISSN 1538-4357
Institute of Physics (IOP)
Research Org:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Country of Publication:
United States
79 ASTRONOMY AND ASTROPHYSICS; galaxies: active; galaxies: clusters: individual (Phoenix); radio lines: galaxies
OSTI Identifier: