Alma Observations of Massive Molecular Gas Filaments Encasing Radio Bubbles in the Phoenix Cluster

Russell, H.R.; McDonald, M.; McNamara, B.R.; Fabian, A.C.; Nulsen, P.E.J.; Bayliss, M.B.; Benson, B.A.; Brodwin, M.; Carlstrom, J.E.; Edge, A.C.; Hlavacek-Larrondo, J.; Marrone, D.P.; Reichardt, C.L.; Vieira, J.D.

Abstract

We report new ALMA observations of the CO(3-2) line emission from the $2.1\pm 0.3\times {10}^{10}\,{M}_{\odot }$ molecular gas reservoir in the central galaxy of the Phoenix cluster. The cold molecular gas is fueling a vigorous starburst at a rate of $500\mbox{--}800\,{M}_{\odot }\,{\mathrm{yr}}^{-1}\,$ and powerful black hole activity in the forms 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 $10\mbox{--}20\,\mathrm{kpc}$ 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. 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.

Citation

Russell, H., McDonald, M., McNamara, B., Fabian, A., Nulsen, P., Bayliss, M., …Vieira, J. (2017). Alma Observations of Massive Molecular Gas Filaments Encasing Radio Bubbles in the Phoenix Cluster. Astrophysical Journal, 836(1), Article 130. https://doi.org/10.3847/1538-4357/836/1/130

• Journal Article Type: Article
• Acceptance Date: Dec 13, 2016
• Online Publication Date: Feb 14, 2017
• Publication Date: Feb 14, 2017
• Deposit Date: Apr 28, 2017
• Publicly Available Date: May 3, 2017
• Journal: Astrophysical Journal
• Print ISSN: 0004-637X
• Electronic ISSN: 1538-4357
• Publisher: American Astronomical Society
• Peer Reviewed: Peer Reviewed
• Volume: 836
• Issue: 1
• Article Number: 130
• DOI: https://doi.org/10.3847/1538-4357/836/1/130
• Related Public URLs: arxiv.org/pdf/1611.00017.pdf