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Accretion Rates onto Massive Black Holes in Four Quiescent Elliptical Galaxies

J. M. Wrobel·J. R. Herrnstein
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Abstract

Four quiescent elliptical galaxies were imaged with the NRAO VLA at 8.5 GHz. Within the context of canonical advection-dominated accretion flows (ADAFs), these VLA images plus published black hole masses constrain the accretion rates to be $ <1.6\times10^{-4}$, $ <3.6\times10^{-4}$, $\le7.8\times10^{-4}$, and $\le7.4\times10^{-4}$ of the Eddington rates. These ADAF accretion rates derived at 8.5 GHz have important implications for the levels of soft and hard X-rays expected from these quiescent galaxies.

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J. M. Wrobel, J. R. Herrnstein. 2000-03-02. Accretion Rates onto Massive Black Holes in Four Quiescent Elliptical Galaxies. https://doi.org/10.1086/312618

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