Limits on the accretion rates onto massive black holes in nearby galaxies

Abstract

The radio emission from supermassive black holes in nearby early-type galaxies can be used to test possible explanations for their low luminosities. We calculate the expected contribution from thermal synchrotron emission from hot accretion flows to the high radio frequency observations of NGC 2300, NGC 1399, NGC 4278 and NGC 4594. We find that, in all cases, and in accordance with our previous findings, hot flows accreting close to their Bondi rates overestimate significantly the observed fluxes. This implies that simply assuming a low radiative efficiency for the accreting gas is not enough to explain their low luminosities. Smaller central densities and accretion rates, as expected in the presence of strong mass loss or convection in the flows, can help reconcile the models with observations. We also show that a significant contribution to the high-frequency radio spectra can be due to non-thermal synchrotron emission from the small scale radio jets observed in these systems, allowing for even lower accretion rates in the inflows. We suggest that these outflows or jets may dump significant energy into the surronding medium close to the accretion radius and so reduce the accretion rates onto these systems. We discuss the relationship between the radio flux and black hole mass for the observed sample and its potential importance for probing accretion models.

14 pages, 5 figures; submitted to ApJ

References in corpus (9)

• Convection-Dominated Accretion Flows
• Self-Similar Accretion Flows with Convection
• Hydrodynamical Non-radiative Accretion Flows in Two-Dimensions
• Low radiative efficiency accretion in the nuclei of elliptical galaxies
• Constraining the Accretion Rate Onto Sagittarius A* Using Linear Polarization
• Radio Sources in Low-Luminosity Active Galactic Nuclei. II. VLBI Detections of Compact Radio Cores and Jets in a Sample of LINERs
• Sgr A* Polarization: No ADAF, Low Accretion Rate, and Non-Thermal Synchrotron Emission
• Hard X-ray emission from elliptical galaxies
• Accretion Rates onto Massive Black Holes in Four Quiescent Elliptical Galaxies

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