Bibcode
Fogarty, Kevin; Postman, Marc; Li, Yuan; Dannerbauer, Helmut; Liu, Hauyu Baobab; Donahue, Megan; Ziegler, Bodo; Koekemoer, Anton; Frye, Brenda
Bibliographical reference
The Astrophysical Journal, Volume 879, Issue 2, article id. 103, 16 pp. (2019).
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7
2019
Journal
Citations
30
Refereed citations
26
Description
We present new Atacama Large Millimeter Array observations of the
molecular gas and far-infrared continuum around the brightest cluster
galaxy (BCG) in the cool-core cluster MACS 1931.8-2635. Our observations
reveal (1.9 ± 0.3) × 1010 M ⊙ of
molecular gas, on par with the largest known reservoirs of cold gas in a
cluster core. We detect CO(1‑0), CO(3‑2), and CO(4‑3)
emission from both diffuse and compact molecular gas components that
extend from the BCG center out to ∼30 kpc to the northwest, tracing
the UV knots and Hα filaments observed by the Hubble Space
Telescope. Due to the lack of morphological symmetry, we hypothesize
that the ∼300 km s‑1 velocity of the CO in the tail
is not due to concurrent uplift by active galactic nucleus (AGN) jets;
rather, we may be observing the aftermath of a recent AGN outburst. The
CO spectral line energy distribution suggests that molecular gas
excitation is influenced by processes related to both star formation and
recent AGN feedback. Continuum emission in Bands 6 and 7 arises from
dust and is spatially coincident with young stars and nebular emission
observed in the UV and optical. We constrain the temperature of several
dust clumps to be ≲10 K, which is too cold to be directly
interacting with the surrounding ∼4.8 keV intracluster medium (ICM).
The cold dust population extends beyond the observed CO emission and
must either be protected from interacting with the ICM or be surrounded
by local volumes of ICM that are several keV colder than observed by
Chandra.
Related projects
Molecular Gas and Dust in Galaxies Across Cosmic Time
Two of the most fundamental questions in astrophysics are the conversion of molecular gas into stars and how this physical process is a function of environments on all scales, ranging from planetary systems, stellar clusters, galaxies to galaxy clusters. The main goal of this internal project is to get insight into the formation and evolution of
Helmut
Dannerbauer