http://arxiv.org/abs/2303.16927
Massive molecular clouds have been discovered in massive elliptical galaxies at the center of galaxy clusters. Some of this cold gas is expected to flow in the central supermassive black holes and activate galactic nucleus (AGN) feedback. In this study, we analyze archival ALMA data of 9 massive elliptical galaxies, focusing on CO line emissions, to explore the circumnuclear gas. We show that the mass of the molecular gas within a fixed radius (500 pc) from the AGNs (M_mol ~ 10^7-10^8 M_sun) is correlated with the jet power estimated from X-ray cavities (P_cav ~ 10^42-10^45 erg s^-1). More specifically, the power is proportional to the average density of the circumnuclear gas. The mass accretion rate of the circumnuclear gas \dot{M} also has a correlation with P_cav. On the other hand, the continuum luminosities at ~ 1.4 GHz and ~ 100-300 GHz have no correlation with M_mol. These results indicate that the circumnuclear gas is sustaining the long-term AGN activities (~ 10^7 yr) rather than the current ones. We also study the origin of the continuum emission from the AGNs at ~ 100-300 ~GHz and find that it is mostly synchrotron radiation. For low-luminosity AGNs, however, dust emission appears to contaminate the continuum.
Y. Fujita, T. Izumi, N. Kawakatu, et. al.
Fri, 31 Mar 23
62/70
Comments: 12 pages, 7 figures