2014/03/17 by B. R. McNamara, McNamara, B. R., H. R. Russell +36
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysics of Galaxies (astro-ph.GA) #FOS: Physical sciences #Galaxies: Formation, Evolution, Phenomena #Stellar, planetary, and galactic studies
paper · pdf · doi:10.48550/arxiv.1403.4249
openalex publication_date 2014/03/17 · openalex created_date 2019/06/27 · openalex updated_date 2026/07/28
We report ALMA Early Science observations of the Abell 1835 brightest cluster galaxy (BCG) in the CO (3-2) and CO (1-0) emission lines. We detect 5× 1010~\rm M_\odot of molecular gas within 10 kpc of the BCG. Its ensemble velocity profile width of ∼ 130 ~\rm km~s-1 FWHM is too narrow for the molecular cloud sto be supported in the galaxy by dynamic pressure. The gas may instead be supported in a rotating, turbulent disk oriented nearly face-on. Roughly 1010~\rm M_\odot of molecular gas is projected 3-10 ~\rm kpc to the north-west and to the east of the nucleus with line of sight velocities lying between -250 ~\rm km~s-1 to +480 ~\rm km~s-1 with respect to the systemic velocity. The high velocity gas may be either inflowing or outflowing. However, the absence of high velocity gas toward the nucleus that would be expected in a steady inflow, and its bipolar distribution on either side of the nucleus, are more naturally explained as outflow. Star formation and radiation from the AGN are both incapable of driving an outflow of this magnitude. If so, the molecular outflow may be associated a hot outflow on larger scales reported by Kirkpatrick and colleagues. The molecular gas flow rate of approximately 200~\rm M_\odot ~yr-1 is comparable to the star formation rate of 100-180~\rm M_\odot ~yr-1 in the central disk. How radio bubbles would lift dense molecular gas in their updrafts, how much gas will be lost to the BCG, and how much will return to fuel future star formation and AGN activity are poorly understood. Our results imply that radio-mechanical (radio mode) feedback not only heats hot atmospheres surrounding elliptical galaxies and BCGs, it is able to sweep higher density molecular gas away from their centers.