2000/07/25 by Martin G. Haehnelt, Guinevere Kauffmann · 234 citations
Physics and Astronomy · #Astronomy #Astronomy and Astrophysical Research #Astrophysical Phenomena and Observations #Astrophysics #Binary black hole #Black hole (networking) #Bulge #Galaxies: Formation, Evolution, Phenomena #Galaxy #Gravitational wave #Intermediate-mass black hole #Luminosity #Physics #Redshift #Spin-flip #Stellar black hole #Supermassive black hole #Velocity dispersion #astro-ph
paper · pdf · doi:10.1046/j.1365-8711.2000.03989.x
published in Monthly Notices of the Royal Astronomical Society 318(3), L35-L38 (Oxford University Press) · 5 pages, LaTeX, 3 postscript figures included; submitted to MNRAS
arxiv created 2000/07/25 · openalex publication_date 2000/11/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Recent work has demonstrated that there is a tight correlation between the mass of a black hole and the velocity dispersion of the bulge of its host galaxy. We show that the model of Kauffmann & Haehnelt, in which bulges and supermassive black holes both form during major mergers, produces a correlation between Mbh and σ with a slope and scatter comparable to the observed relation. In the model the Mbh−σ relation is significantly tighter than the correlation between black hole mass and bulge luminosity, or the correlation between bulge luminosity and velocity dispersion. There are two reasons for this: (i) the gas masses of bulge progenitors depend on the velocity dispersion but not on the formation epoch of the bulge, whereas the stellar masses of the progenitors depend on both; (ii) mergers between galaxies move black holes along the observed Mbh−σ relation, even at late times when the galaxies are gas-poor and black holes grow mainly the by merging of pre-existing black holes. We conclude that the small scatter in the observed Mbh−σ relation is consistent with a picture in which bulges and black holes form over a wide range in redshift.