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arXiv · 1909.10821

Coevolution (Or Not) of Supermassive Black Holes and Host Galaxies: Black Hole Scaling Relations Are Not Biased by Selection Effects

John Kormendy
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Abstract

The oral version of this paper summarized Kormendy & Ho 2013, ARA&A, 51, 511. However, earlier speakers at this Symposium worried that selection effects bias the derivation of black hole scaling relations. I therefore added -- and this proceedings paper emphasizes -- a discussion of why we can be confident that selection effects do not bias the observed correlations between BH mass M_BH and the luminosity, stellar mass, and velocity dispersion of host ellipticals and classical bulges. These are the only galaxy components that show tight BH-host correlations. The scatter plots of M_BH with host properties for pseudobulges and disks are upper envelopes of scatter that does extend to lower BH masses. BH correlations are most consistent with a picture in which BHs coevolve only with classical bulges and ellipticals. Four physical regimes of coevolution (or not) are suggested by Kormendy & Ho 2013 and are summarized here.

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John Kormendy. 2019-09-24. Coevolution (Or Not) of Supermassive Black Holes and Host Galaxies: Black Hole Scaling Relations Are Not Biased by Selection Effects. https://doi.org/10.1017/s1743921319008500

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