Deep Chandra, HST-COS, and Megacam Observations of the Phoenix Cluster: Extreme Star Formation and AGN Feedback on Hundred Kiloparsec Scales

McDonald, M.; McNamara, B.R.; van Weeren, R.J.; Applegate, D.E.; Bayliss, M.; Bautz, M.W.; Benson, B.A.; Carlstrom, J.E.; Bleem, L.E.; Chatzikos, M.; Edge, A.C.; Fabian, A.C.; Garmire, G.P.; Hlavacek-Larrondo, J.; Jones-Forman, C.; Mantz, A.B.; Miller, E.D.; Stalder, B.; Veilleux, S.; ZuHone, J.A.

doi:10.1088/0004-637x/811/2/111

Deep Chandra, HST-COS, and Megacam Observations of the Phoenix Cluster: Extreme Star Formation and AGN Feedback on Hundred Kiloparsec Scales

McDonald, M.; McNamara, B.R.; van Weeren, R.J.; Applegate, D.E.; Bayliss, M.; Bautz, M.W.; Benson, B.A.; Carlstrom, J.E.; Bleem, L.E.; Chatzikos, M.; Edge, A.C.; Fabian, A.C.; Garmire, G.P.; Hlavacek-Larrondo, J.; Jones-Forman, C.; Mantz, A.B.; Miller, E.D.; Stalder, B.; Veilleux, S.; ZuHone, J.A.

Authors

M. McDonald

B.R. McNamara

R.J. van Weeren

D.E. Applegate

M. Bayliss

M.W. Bautz

B.A. Benson

J.E. Carlstrom

L.E. Bleem

M. Chatzikos

Professor Alastair Edge alastair.edge@durham.ac.uk
Professor

A.C. Fabian

G.P. Garmire

J. Hlavacek-Larrondo

C. Jones-Forman

A.B. Mantz

E.D. Miller

B. Stalder

S. Veilleux

J.A. ZuHone

Abstract

We present new ultraviolet, optical, and X-ray data on the Phoenix galaxy cluster (SPT-CLJ2344-4243). Deep optical imaging reveals previously undetected filaments of star formation, extending to radii of ~50–100 kpc in multiple directions. Combined UV-optical spectroscopy of the central galaxy reveals a massive (2 × 109 M⊙), young (~4.5 Myr) population of stars, consistent with a time-averaged star formation rate of 610 ± 50 M⊙ yr−1. We report a strong detection of O vi λλ1032,1038, which appears to originate primarily in shock-heated gas, but may contain a substantial contribution (>1000 M⊙ yr−1) from the cooling intracluster medium (ICM). We confirm the presence of deep X-ray cavities in the inner ~10 kpc, which are among the most extreme examples of radio-mode feedback detected to date, implying jet powers of 2–7 × 1045 erg s−1. We provide evidence that the active galactic nucleus inflating these cavities may have only recently transitioned from "quasar-mode" to "radio-mode," and may currently be insufficient to completely offset cooling. A model-subtracted residual X-ray image reveals evidence for prior episodes of strong radio-mode feedback at radii of ~100 kpc, with extended "ghost" cavities indicating a prior epoch of feedback roughly 100 Myr ago. This residual image also exhibits significant asymmetry in the inner ~200 kpc (0.15R500), reminiscent of infalling cool clouds, either due to minor mergers or fragmentation of the cooling ICM. Taken together, these data reveal a rapidly evolving cool core which is rich with structure (both spatially and in temperature), is subject to a variety of highly energetic processes, and yet is cooling rapidly and forming stars along thin, narrow filaments.

Citation

McDonald, M., McNamara, B., van Weeren, R., Applegate, D., Bayliss, M., Bautz, M., …ZuHone, J. (2015). Deep Chandra, HST-COS, and Megacam Observations of the Phoenix Cluster: Extreme Star Formation and AGN Feedback on Hundred Kiloparsec Scales. Astrophysical Journal, 811(2), https://doi.org/10.1088/0004-637x/811/2/111

Journal Article Type	Article
Acceptance Date	Aug 21, 2015
Publication Date	Oct 1, 2015
Deposit Date	Oct 28, 2015
Publicly Available Date	Nov 12, 2015
Journal	Astrophysical Journal
Print ISSN	0004-637X
Electronic ISSN	1538-4357
Publisher	American Astronomical Society
Peer Reviewed	Peer Reviewed
Volume	811
Issue	2
DOI	https://doi.org/10.1088/0004-637x/811/2/111
Related Public URLs	http://ukads.nottingham.ac.uk/abs/2015ApJ...811..111M