Skip to main content

Research Repository

Advanced Search

Molecular Gas Filaments and Star-forming Knots Beneath an X-Ray Cavity in RXC J1504–0248

Vantyghem, A.N.; McNamara, B.R.; Russell, H.R.; Edge, A.C.; Nulsen, P.E.J.; Combes, F.; Fabian, A.C.; McDonald, M.; Salomé, P.

Molecular Gas Filaments and Star-forming Knots Beneath an X-Ray Cavity in RXC J1504–0248 Thumbnail


A.N. Vantyghem

B.R. McNamara

H.R. Russell

P.E.J. Nulsen

F. Combes

A.C. Fabian

M. McDonald

P. Salomé


We present recent ALMA observations of the CO (1–0) and CO (3–2) emission lines in the brightest cluster galaxy of RXC J1504.1−0248, which is one of the most extreme cool core clusters known. The central galaxy contains $1.9\times {10}^{10}\,{M}_{\odot }$ of molecular gas. The molecular gas morphology is complex and disturbed, showing no evidence for a rotationally supported structure in equilibrium. A total of 80% of the gas is situated within the central 5 kpc of the galactic center, while the remaining gas is located in a 20 kpc long filament. The cold gas has likely condensed out of the hot atmosphere. The filament is oriented along the edge of a putative X-ray cavity, suggesting that active galactic nucleus activity has stimulated condensation. This is energetically feasible, although the morphology is not as conclusive as systems whose molecular filaments trail directly behind buoyant radio bubbles. The velocity gradient along the filament is smooth and shallow. It is only consistent with freefall if it lies within 20° of the plane of the sky. The abundance of clusters with comparably low velocities suggests that the filament is not freefalling. Both the central gas and filamentary gas are coincident with bright UV emission from ongoing star formation. Star formation near the cluster core is consistent with the Kennicutt–Schmidt law. The filament exhibits increased star formation surface densities, possibly resulting from either the consumption of a finite molecular gas supply or spatial variations in the CO-to-H2 conversion factor.


Vantyghem, A., McNamara, B., Russell, H., Edge, A., Nulsen, P., Combes, F., …Salomé, P. (2018). Molecular Gas Filaments and Star-forming Knots Beneath an X-Ray Cavity in RXC J1504–0248. Astrophysical Journal, 863(2), Article 193.

Journal Article Type Article
Acceptance Date Jul 9, 2018
Online Publication Date Aug 23, 2018
Publication Date Aug 23, 2018
Deposit Date Sep 6, 2018
Publicly Available Date Sep 6, 2018
Journal Astrophysical Journal
Print ISSN 0004-637X
Publisher American Astronomical Society
Peer Reviewed Peer Reviewed
Volume 863
Issue 2
Article Number 193


Published Journal Article (1.4 Mb)

Copyright Statement
© 2018. The American Astronomical Society. All rights reserved.

You might also like

Downloadable Citations